While, sadly, I can't help with your question, it would be of interest to see photos of the other side of the pistol, and a top, bottom and front view as well. (That might also be of some use to those here who might be in a better position to help with identification.)
I'll do that right away. I had to shrink them quite a bit so I'll figure out and upload shortly I had it all on Google drive at 108 mp so it's been a challenge to shrink 🙂