Why not fit power mirrors from something else? The Vanagon ones are ugly
and seem vulnerable to damage.

I am fitting a nice set of springloaded chromed (plastic) units from a
Japanese-market Hilux Surf SSR.

These are window-mount. To adapt them to the VW doorskin mounts I have had
aluminum mounts cast. I had to get chunks of balsa and carve them to make
mount blanks, then gave these to the foundry.

When I get my van back I will ensure the castings fit the doors, then get
the necessary machining done, after which it will be a matter of smoothing
the rough metal with polyester or epoxy filler and spraying with, say, VHT
Black Oxide Case Paint.

These mirrors will be far more reliable than the VW ones, I'm sure.