Don't hang the old girl up just yet.
If you can't source the correct part, or make one, there is a mod that you can do to keep the gun in service.
Go to Princess Auto and get one of their $6 bags of 100 coil springs. They are all types, mixed: light, medium, heavy, compression, extension and torsion, and all in relatively small sizes.
You can clip one of the short, fairly heavy compression ones in half, wedge it in where it is to go and cement it in place with epoxy. Horrid, I know, but it will work.
A better fix, using the same spring, is to drill a tiny hole into the back side of the recoil shield, just INTO it but not all the way through. BEND to 90 degrees the END of one of the medium-heavy compression springs so that the tip of the spring will insert into this cavity: you now have a solid point of contact with the frame of the gun. Clip the spring to about 3 turns and CLOSE it, then use your Dremel to face it off perfectly flat. Now a single drop of epoxy will hold it against the forward-moving face of the latch. Result: one working revolver.
Horrid, I know, but it works.
Hope this helps.
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