I didn't know what a Macrostat is so looked it up. Now I know what it is and that I don't need one/wouldn't use it if I had it. So I'm not a customer and there may not be many. But there are probably still some Alpa collectors. Is there a club?
It is a long shot, but if anyone has access to that collectors' market it is Peter Koeln of Westlicht Gallery. Make an inventory, send it to him, ask him whether he's interested and for advice.