Auto Atlanta, Sierra Madre, Stoddards, Einmalig, & others carry them.
Buy 2 now so that they match, & put the odd one in your glovebox for a spare in the emergency.
As Mark said - make sure that the crank, guides, regulator, etc. are cleaned then relubed with clean grease so they work less hard.
If you look at the SMC ones on the page linked below, the chrome shank one was used 70-72 & some early 73s, the thin black shank was 73-74 & the fat shank was 75-76 MYs IIRC (there was probably some inter-MY mixing on the last 2 types as well) - contrary to what they list no there. And they would've tracked with the VW change over MYs as well, & they're basically VW parts, so you can find them at some VW parts houses too.
FYI with pix -
http://www.sierramadrecollection.com/914-9...or-Panels-c957/ Tom
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