Jon,
To help your search, it would be the same DS mirror with the sharp 90 degree angle arm as used on all 914s /4 & -6 from 70-71 MYs (nothing is specific 914-6, & IIRC the part nos. aren't date stamped on the mirrors, but maybe they are).
You might try AASE parts in Ohio, since they have a stash of NOS parts, as well as try George at Auto Atlanta & Stoddard's (also in OH), & Rich Bontempi at HPH (High Performance House in Redwood City CA), & perhaps German evil-bay.
You're looking for long NLA hens-teeth at this point, & if you find anything NOS it will be pricey!
PS - Since you're in Oakland, it would be well worth your while to call Rich Bontempi at HPH & make a trip over to his facility in Redwood City with your parts list in hand to see what he may have in NOS & excellent/good condition used parts. Chat with him about your project, & he's more than happy to talk about his 914 racing days! ;-)
Happy Hunting!
Tom
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