The bbls look reblued.,,if that makes a difference.

I think it's been apart. The screws are buggered a little and not lined up anymore. The left side cap covering access to the barrel pin is over tightened. Usually a sign it's been off,,and back on.
Just judging from the pics (and it's just that), I'd guess that the receiver was cleaned up a bit to it's present grey color. Perhaps a light carding wire wheel while disassembled. Then some cold blue added to add in some color.

The blue on the trigger plate is worn from the inaccessable area up close to the guard,,but yet still in tact further out on the bottom of the gun where the rest of the rec'vr is worn.

I just think the gun has been dolled up and wonder about the internals.

Just some things I see looking quickly over the pics...

Czech proof and no name,,how do they know it's a German gun.
Does it have German proofs also? Just wondering.