Well you got a treasure! Congratulations on becoming the next caretaker.
Getting it insured at a Full Appraised "Agreed Value" policy with Hagerty, Grundy, or one of the others that specialize in classic Porsches etc. should be your 1st priority - even sitting as is.
There are several insurers who advertise in the PCA Panorama magazine, & joining PCA is worth the $46 for that excellent magazine alone, in addition to the other member benefits, activities, Porsche parts discounts, etc.
Order a COA from PCNA while your at it (small PCA discount), & hopefully you have the original window sticker from your uncle to send them a copy with your application, since they're notorious for F-ing them up!
As others said, get documentation to confirm the 15K miles, or whatever it is. At this point even115K would be good, & 15K would be uber-rare.
You'll want to try to find an old school Porsche, VW mechanic near you who is well versed in 914s to help guide you with what to do, & with what parts.
Also as others have said, look at what maintenance items would've been done over time since stored, & do those - primarily the soft rubber parts, hoses & lines which would've been aged by now to where they won't be safe: brake, vacuum & fuel lines, master cylinder & brake caliper seals, etc. Most of these can still be had in stock form (see fuel lines note below).
There is a chance that the tunnel plastic fuel lines may be okay if only 15K miles then stored, but if they need replaced, then the SS ones would be acceptable without damaging originality value. So do them if needed with the Tangerine ones or similar.
The used & reconditioned fuel tank noted by others from another 73 1.7 or 2.0, or a 74 2.0 or 1.8, or earlier 914/4 1.7 would be the way to go, since I'm not aware of any repro tank anyway. Check the mesh fuel "sock" at the tank outlet too, & replace if necessary.
I think that you can get the square box type fuel filters still from VW parts suppliers, & IIRC GoWesty carries them for the early aircooled Vanagon 2.0s & late Bay Window 1.6 & 2.0 Vans.
Once all rubber lines & the tank etc. are refitted, then just try the fuel pump, as it may be fine, or may just need a flushing of the old fuel & "varnish" or sludge from the old fuel. It may not need to be replaced. If you need to replace it, then hopefully you can find an NOS correct 3-port pump, or a good used or rebuilt one.
Don't try to start the engine nor drive the car until all of the recommissioning items are done, new fluids all around, etc
Depending on when your 73 was built, it could have 1 or 2 Recalls on it, that I'm betting weren't done since it was driven so little then stored (if 15K). If either or both were never done, then Porsche will still need to do them at their cost, but you'll need to call PCNA to arrange for one of their Service DMs to come out to your place to inspect the car, then will schedule you for the repair(s).
1. - ALL 914s are subject to the HO Recall, which replaces the cloth covered fuel lines with rubber exterior ones, & replaces the "T" shaped battery cover with a full battery rectangular cover.
2. - The 73s up to about December 1972 production dates +/- are also subject to the BO Recall, which involves inspecting that the correct "hub-centric" wheels were fitted on the car, which have a groove of inset around the inside of the center hole to seat properly on the new-for-73-MY self-centering front hubs. The proper wheels will end in a xxxx.01 part number on the back, the wrong ones with xxxx.00.
Another item you may want to do, which was the subject of a Porsche Service Bulletin, is the relocation of the fuel pump from the mid-engine compartment, up to the front of the car up behind the steering rack cover plate, just below the fuel tank compartment & just to the right/passenger side of the round portal in the front firewall where the fuel lines from the tunnel daylight. Auto Atlanta sells a FP relocation kit which is essentially the same as what the factory supplied to the dealers to move the pump. It was done to eliminate vapor lock due to the pump & lines getting too hot in the engine compartment, & applies to ALL 70-74 914s of both 4 & 6 flavors (the factory relocated them to the front for 75-76 MYs & changed to a 2-port pump to solve that problem). You'll want to do the fix as per the Service Bulletin, & not some of the other alternatives which others have done on here, in order to preserve it's originality.
If/when the Heat Exchanger/Exhaust Pipes (HE) need replacing, then you'll probably have to use the SSI stainless steel HEs, but you can have them painted in the Porsche Exhaust Grey color to look closer to OE. Dansk makes/sells those & the 2.0 "Banana" Muffler replacements as the current OEM, & they're also sold through other Porsche dealers & parts retailers. There's an outside chance that you may find either in an NOS from somebody, but few & far between.
Tires will be another issue, since the Michelin XAS 165HR15 tires are tube type, as are IIRC the Pirelli of the day, & they're pricey; while there is a non-period Blockley 165HR15 with the dog-bone tread pattern very similar to the Dunlop SP57s & Semperit M401/M501 tires of the day. Try Lucas Tires in Long Beach CA online, & note that any tire which you can find on their UK sister company Longstone Tyre can be brought here by Lucas. I think I'd stick with one of those 3 tires, given your extremely low mile & original 914, but you can read through the Wheels & Tires nailed thread in the Originality & History (O&H) Forum on here.
These recall, service bulletin & substituted parts items are generally considered acceptable for originality.
There are also lots of other good guidance in the O&H under nailed threads, including the tires & wheels, "The few, the rare..." (on all original cars - get pix of yours on there too), "The Legend of the 914S", etc. which will help guide you. Other good resources include Jeff Bowlsby's Classic 914 website, & p914.com (& .net & .org).
Do a good deal of research to see what is original on your car, before you start mucking around, so that you know what to keep & what not.
Also, keep that beauty garaged & out of the hurricane/tornado/T-storm flood waters/winds/etc. down there in the FL Panhandle.
Good Luck!
Tom
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