Ah, so a lip or tab on the grip that slips under the side plate must've broken off (since the screws look like they've never been messed with). Well, I do have a block of walnut sitting around doing nothing...
I wonder if the timing can be revived in any way (again, it looks worn, not deformed). I dunno, TIG-ing a little blob back onto the timing star and hand then whittling them back down to where it cams properly? I suspect the pawl spring may be weak/broken (hammer seems like it releases way too early) and that could the real factor in the timing problems.
"Guns don't kill people; people kill people. Guns protect people from people with smaller guns." -Stan Smith