Charlie,
You have a M1906 American Eagle. These were made for the American market. Everything looks correct except the mag, which should have a plain bottom or one that is stamped GERMANY. Your mag is probably a WWI military. The external #'s (last two digits of the S#) will be stamped in the commercial (hidden) style, on the bottom edge of the takedown lever and sideplate. To see the other #'s you will have to feild strip the gun. If you are uncomfortable posting the full serial # here, you should at least email the info to Dwight Gruber for his commercial database.
http://forum.lugerforum.com/showthread.php?t=14277