Is the sideplate 'x'd out?
Is there an 'X" on the left receiver?
It might be an East German Vopo, since it looks like it doesn't have a dip blue, it makes me think East german instead of russian / also, if top matches and bottom matches, that would not be a good indication of either, as they force match (to ensure they worked).
So, likely two guns got mixed / but I would buy these at $400 any day of the week, nice score, where did you come across it?
Ed