Hey there Revill. Welcome.
There are still a few former MZ dealers here in the US that can order parts, when needed. I bought my Baghira at SF Moto in San Francisco, and they're still a reliable source for parts (well, as long as parts remain available at all, that is).
On this one, though, I don't think you'll need to go that far for the part. Although I don't know exactly what the part number is, I understand that the fan switch is somewhat universal, and you can probably pick one up at your local auto parts store, once you find the car model that uses the same one.
One of our European friends mentioned Opal as bing one of the cars that had the same switch, but they're about as easy to find parts for in the US as MZ.
Maybe someone has tracked down a car model that has the right switch. Otherwise, you might just take yours in to your local parts counter and see if they'll help you match it.
BTW, if you do still want to get the MZ part (or are looking for other MZ-only parts), you might try this former MZ dealership in Houston:
MPH Cycles, Inc.
16510 Park Row
Houston, Texas 77084
(281) 647-6557
mike@mphcycles.comI know they're not that near to Austin, but maybe they know of a former MZ dealer closer to you who's still willing to order parts.
Good luck with that. Anyone else?