Yeah, that's not right. The stamps look totally wrong to begin with, and don't quote me on this but but I'm pretty sure that it was all Weimar eagles in 1936, with the Nazi proof marks getting phased in from 37-39. I don't think that Oberndorf was putting Nazi eagles on their Lugers until 1939.
Either way, the worst part is that they're in totally the wrong place. It should be opposite, where you've already got your other inspection and firing proofs. That spot on the receiver and barrel should be blank.
I don't have a 1936 S/42 to compare, but here's the same spot on my S/42 G-Date (1935). Also the proofs and stamps on the reverse side of the frame, where they should be.
I'll add that some of the other markings look a bit soft to me, and I'm not in love with the bluing. I'm far less confident on this, as judging bluing is always an art form at best and difficult as hell looking at photos, but it doesn't sit well with me, especially on the barrel/upper assembly.