Black Leatherette (vinyl) is probably the easiest to find replacement material, individual & full interior kits.
I don't know this group & they may be just fine.
The price sounds too low for "real leather" - so maybe it's not, or a very thin mm skin of leather glued to a backer, which I see on stuff from China & other low cost mfgrs. etc. of "leather" items, which then wear out, tear, crack, delaminate, etc. in a very short time. I see that all the time on Wallymart, Okaymart, Tar-get, etc. shoes, clothes, belts & other crappy suedo-leather-goods!
Evil-bay vendors & returns can be a royal PITA too!
However, first I'd check price & availability online with the known quantities who've redone a boatload of 914s - including at: Lakewell in Belgium, Autos International in Fallbrook CA, & World Upholstery in Ojai CA (or somewhere up there by Ventura/Camarillo/S-Barbara).
If they have full sets, individual pre-fitted items &/or raw material which is a close match to your OE black, then you can maybe do a piece now, & others later as you can afford them - then they will probably match pretty good (but .... dye lots can vary, texture can vary in batches), & the first one will probably not only last until you get to the next part to restore - but also last for another 10-20+ years of real life car use & aging!
Just my HO!
Tom
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