I guess I'll have to keep looking. I mint Sinar X would be really neat, but I haven't seen any. Granted I've only looked on Ebay since I don't know where else to look. But mostly all I've found is beater equipment, or "mint" stuff from some place in China that makes my scam alarm tingle.
Regarding new parts or servicing of Sinar gear, apparently Precision Camera Works is the place (particularly for Arca, but also Sinar). But does Sinar even have a north American distributor anymore? I don't think Sinar-Bron exists anymore. There's something called Hasselblad-Bron, but nothing about Sinar on there.