Here is a vintage 1970's Berg Larsen 'straightbill' bullet chamber tenor mouthpiece. It is stamped 100/1 SMS and measures .095" on my gauge.
It isn't clear if this piece is original but what is certain is that the table retains some of the original milling marks, but the rails appear smooth which indicates it likely had some work in the past. Bergs can have remarkably long facing lengths but this one breaks at 25mm and doesn't have work done to the tip.
This is the Sonny Rollins type with the straight beak and bullet chamber.