You wont get lucky. The chuck you have has a serial number. There isnt another Union #2 D999 chuck out there. All chucks have their jaws factory ground in their respective bodies for parallelism and centrality. And are then stamped to keep them together. If you sent it back to the factory they could make a new jaw and grind it to suit. The cost for that will be in excess of what a new chuck will cost. The best you could do is find a jaw that fits and grind it yourself. Or weld in some new teeth and machine/grind/file to suit. You will be better off tracking down a replacement chuck. Do you have the other set of jaws for your chuck?
Cheers Phil
