In addition to 914Rubber (I think that 914A&P is now sold thru them) - the other usual suspects for 914 seat kits are Autos International (AI) in Escondido CA, World Upholstery (WU) in Ventura/Oxnard CA, & Lakewell.com in Europe.
AI does the interiors, but shipping the parts ot/from CA may be prohibitive, so kits or bulk material in adequate quantities for all parts shipped to you then get a local upholstery shop that does Porsches can do them for you (check with local PCA members for referrals there, in addition to here).
If you have the Beige (Tan) interior, then Lakewell is probably the only source now to get the proper 70 & 72-74 Basketweave vinyl matching the smooth Leatherette vinyl, & possibly for the correct 75-76 Brickweave - & that may be the case for the Brown interiors too (AI & WU stopped carrying the Basketweave a few years back).
You don't show what year 914 you have - good idea to put that in your sig. & profile, so folks can see the year & model to help you better.
Good Luck!
Tom
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