How about improved receiver for TT-33 to make it similar to 1911? It can be 80% kit so we could match it perfectly to the slide and internal parts such as trigger group.
Below is my gun that has original receiver that was butchered (some extra metal, etc) to get the proper look. the mag also had a butt plate made to fit nicely.
Steel is a material, but design is quite simple (it's quite simple gun in the first place), so milling is not that hard. All is needed is to design the grip. At least you can use my picture for inspiration. This would be a really nice kit.
PS. If you need a stripped receiver, I can get it for you if needed.