Could anyone help identify these stampings?

[markbritt]

I have a 1918 luger (brother-in-laws) that he picked up a few years ago. The luger is 100% matching, but there is an import marking on the barrel and the trigger plate had a number etched on it with an electic pen (now removed). In addition, the finish was a disaster. He asked me to refinish it and hot blue it for him. I have stripped down the frame and barrel and notice there are 5 markings on the receiver/slide right side. Can anyone identify these for us?

Thanks,
Mark