Ok, you are correct, top and bottom are from two guns.
Not unknown, I have owned at least a couple of them (my brother owns one that I bought as my 2nd luger
)
The top half was just as I said above, crown N (commercial) and army accepted and the sear safety on the left shows it went into police service. No one can say why the bottom is different, likely was done by some US GI's cleaning guns together, but who knows?
The P08 on the left is a Mauser frame, so the bottom is newer than the top.
The army style army holster has the S.H. on the rear?
Ed