IMHO, you're best bet will be to get them NOS from one of the old school shops for the actual EFI components. at the following -
Rich Bontempi @ HPH (High Perfomance House) Redwood City CA
Maybe someone at Sierra Madre Collection in Pasadena CA
Brad Mayuer @ 914LTD Peoria IL
someone at Stoddards in OH
George Hussey @ Auto Atlanta GA
Both Rich & George have huge parts stashes, & Brad too AFAIK.
Make sure to match all the EFI parts p/n's to your 74 using the proper OEM parts where possible. Download the Porsche 914 PET Parts Manual to get the correct parts, if you don't have one on hand.
http://www.porsche.com/all/media/pdf/origi...USA_KATALOG.pdfIf not, then you may be able to find some repros - such as IIRC 914Rubber is making a repro xx.012 CHT for the 74-76 2Ls, but it's not on your list.
The airbox is okay to get used, & Bruce Stone/bdstone on here may have a nice one used &/or restored for your era 74 2.0 (most probably it had the one with the stamped bands across the short-way of the top cover).
Good Luck!
Tom
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