I'm probably going to step on some toes but here goes....DO NOT I repeat DO NOT send it to Youxin Ye....unless of course you want an oil dripping camera returned..

I sent him a IIIf RD and it was returned with oil saturated curtains and dripped oil when I removed the base plate..

As others have said Don Goldberg is good but a bit backlogged so it may take a few months..