I have successfully used brazed to weld a trigger guard back together after sectioning out the bow, and a right hand cast brass patch box lid that I made into a left hand lid. Maybe I was just lucky, i got it up to heat and when things started flowing I kept the torch and rod moving heaping it on so I would have enough to file back, It worked. Not for the faint of heart but it is doable. Good luck!!!!!
Robby