Auction Arms is a good gage to determine the value of the gun, but let me say, the market for both the P-38 and Luger is very fickled, they can go from one extreame to another overnight. There is getting to be more interest in the guns, but fairly recent a bunch were dumped on the American market from several of the old soviet bloc countries. Your gun as a "bring back" without import marks will sell higher than the recent imports.
I have one of each that I picked up in Germany back in the sixties. I paid $100. for each of them, I also bought an FN Browning, factory reconditioned at the same time for $70............I wish today I had bought all they had...........Hind sight is always 20/20. :roll: