They were generally pretty careful about marking the daylights out of the rifles, friend. I have only run into a single issue 1910 which doesn't have the butt defacd by a whack of markings and has never had them there.... and I own that one.

It i entirely possible that your rifle never saw military service at all.

That rear sight is definitely NOT the issue sight. It is a Target sight of a type which is more than just a bit scarce, alhough you will find a few of them with Military markings on the sight itself (as with yours). Issue sight was the Ross Battle Aperture Sight which worked much like this one but was a lot smaller.

Hope to get back to you later. Right now, this machine is giving troubles.

NICE rifle!
.