I replaced one, but – darn it! – I can’t remember what motor I got ..except that it’s white. I looked online and found one; simples. I’m not on the boat right now, so I can’t look at the motor and see what it is, but I’d guess that it was probably sold by Vetus, or by one of the usual chandlery companies.
It was simple – as far as I remember – to do: just unscrew a locking ring and it pulled right out of the windscreen (though first I had to remove the wiper arm, of course!)
I seem to remember that there was a small wiring diagram, and a pin or contact had to be (re)moved to make sure that the arm wiped in the appropriate direction.
If I can find any further info, like and invoice or receipt, I’ll post further info ..but I remember that it wasn’t hard to find a suitable w/w motor!