Re: ww2 ppk
My sources date the slide to 1941. I know of no way to "complete" a slide except by buying a frame and all the parts, which, if it could be done, would cost much more than buying a complete gun, and the frame would be very unlikely to match the slide serial number.
The horrible fact is that many people have bought a part of a gun, or a gun missing parts, and attempted to "complete" it. In almost all cases, the effort proved futile and the parts or partial gun remained as purchased until the owner's heirs sold it to someone else who was going to "complete" it.