6 point star marking

[mystical_tutor]

While trying to check the details on this gun I found something that must be a post-Costanzo mark. At least I can not find it in his book.

It is on the front sight base and it is a 6 point star. There is nothing inside the star, actually not enough room for anything.

DWM
1910
Police sear and mag safety
Unit mark 2. G. U.

The closest thing is #108 which is a much later marking and has the letter c in it for the Israeli marking.

I haven't been active in collecting for about 20 years so this may be a common thing that I just don't know about but any information will be appreciated.