David Chicoine is probably the go-to guy for that, but a fix would likely involve machining a replacement hook and then welding it on. Then the gun would have to be totally refinished, which with its funky engraving and the scene on the sideplate, would probably be very difficult and time consuming, and therefore very expensive.
oldwestgunsmith.com


I'm having Chicoine work over and refinish a S&W DA .44 that I got cheap, and the final bill will be far more than the gun will ever be worth. I would've been much better off just selling the dang thing as-is, but I couldn't resist "saving" it.

I think this MH is probably best left as-is, although it'd be nice to find a replacement for that missing screw.