As with everything in life, you have to shop around.
I've used all the vendors listed (914Rubber, Pelican, Automobile Atlanta) and quite a few that are no longer with us (Performance Products, Automotion, Tweeks) and others I've long since forgotten.
The one thing I will say for AA is that they were in this game since the get go. Sometimes they have (or tooled up and made) parts that you couldn't get anywhere else. The prices on their site are sometimes confusing. AA lists OEM Porsche parts alongside aftermarket parts. Sometimes multiple variants of aftermarket parts, each at different prices. Sometimes the aftermarket part is the same as the OEM Porsche part but costs way less. You just have to shop carefully and if in doubt talk with George.
With demand and prices for 914's rising, others have begun tooling up parts (914Rubber, Restoration Design, Dansk, URO, and others) which is a great thing.
Often the parts are stocked across vendors and the mark up varies depending on who is reselling what part.
I know everyone likes to complain about middle man mark ups, but, sometimes it just makes more sense to order one or two marked up parts as part of a larger batch order than pay seperate shipping across two or three separate vendors.
Again, just need to do the math and shop around.
We are lucky to have so many vendor choices now!
I appreciate all of them for what they do.
No shame in them making some money as they support us. Without profit to the vendors, they don't have money to survive and to reinvest into tooling up more parts as the list of NLA parts contrinues to grow.