Ok. It was a long shot. After finding out this trem was only ever used on this one model guitar, that was made for less than a year, I didn't figure to get a response. In all my searching I only saw one other guitar with this bridge. Rik Emmett (Triumph) had two custom Yamaha SG3000's made with trem. The trem n these guitars is a gold plated version of the trem used on the SBG1300TS. But that's it. No other reference to this trem anywhere.
No response from Yamaha on the matter either. Even though they did respond to another question that I asked a day later. They just ignored the trem inquiry!?!
So my next move will be to take the guitar to a music store and try all the screw in trem bars they have. If one fits I'll try to order it. If not I'll either modify the bridge to fit a modern bar or make a bar from a piece of rod stock.
Thanks for the 100+ views from people wanting to help. And sorry the question was so obscure.