New to forum - my 1938 P08

[Mac Cat]

There are a lot of moving parts in just the upper toggle assembly.
Get the pins out and clean it a lot. It should move smoothly, like links in a bicycle chain.
Lugers don't handle mud and dirt well.
A mis-matched part could be a problem, but it looks like it's all original, so far.
You photos are nice and sharp, but very dark. It's a challenge to photograph well.
Take it outside on a sunny day or use some of the new LED lighting strips.