This gun just does not look like it came through Waffenfabrik-USA (North or Southwest or Southeast...)...IMO.
The C/M's seem to be the early variety with the 3-lobes in the center of the crown. If I recall on the informative postings on Jan's Board, the 3-lobe crowns both "float" and are also seated directly on top of the M's.
Here is a link to that discussion thread :
http://luger.gunboards.com/topic.asp?TOPIC_ID=421
The later crown style with the "pentagon" in the middle of the crown is the one on later M1908 and M1914; that I think are not supposed to "float" above the M's.
I could be all wrong...have been before. Especially since I do not even own one (1) Navy. Will wait for the Navy guys to chime-in...
p.s. Here is a photo from E. Bender's big book...showing the "pentagon" style stamps with their integral design which results in the crown not-floating above the M's.