[Dominik]

I should have 2 (if not more) rear upright castings here in Cape Town.
I verify in the week. Also, I can get them cast here, or in Germany. But only from 10 pieces up.

You want some fries, I mean drawings with that? We can talk.
PM me. Your timing is right. I get mine machined in about 3 weeks, but for another wheel bearing.

Generally, however, I advise to use and alter what you have on the local market.
Especially in the US I would contact the chassis/suspension builders and use their control arms. It's so much cheaper.

Unless you like originality...