ctc...
If you're just looking for "A mirror" to fill in the blind spot, then you can use any left mirror on the right "flipped" & buy one used. I don't see many for sale used on here nor other usual seller sites.
If you want the "real" convex passenger side mirror, then AFAIK they're still available from Porsche - as are the driver side ones, so you could buy both new if you want nice-n-shiny.
The factory passenger side mirror was only 10% convex - so not much different than the flat driver side mirror. BTW it can also be flipped for RHD cars, when 914s were converted to RHD in the UK, Australia, etc.
Cheers!
Tom
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