The engraving appears cut w/an air assist engraving tool to me. That would put it around 1970 and forward w/the GraverMeister (GRS mfg) coming around about then. Very popular.
The border punch tool, called a 'mules foot punch' in the trade was a common off the shelf punch that was sold for years by a couple different engraver supply companys.
NGraver in CT sold it since the late 60's until just this year or last.
I have one still on my bench. I ground the small verticle dash out of the stamp inside the inverted U on the last job I used it on in the 90's to make it look at least a little different from the over the counter edition.
I added a hand cut accent mark inside the U to replace it,,just a smaller U inside it.. That was on a Deluxe Grade 1903 Winchester that I did a #8 Winchester pattern on for a customer.
Unfortunetly the gun got resold as an original.
With letters of testimony to it's originality of factory Winchester engraving by Angelo Stokes from 3 different 'experts', I spotted the rifles in a display at an OGCA show a couple years back.
You know your own work when you see it.
told the guy behind the display the story. Didn't seem like he believed me much, but the gun was gone the next trip around the hall.
I later found this closed auction on line by accident of that same rifle....Maybe where he got it..
Extremely Rare Factory Engraved Winchester Deluxe Model 1903 Semi-Automatic Rifle
Note the 'originality claims' dispite no factory records exist.
I figured they just removed my mark from it and let it fly. Another reason I don't believe anything I see anymore. I've seen too much of this stuff I guess.
That includes guns, boxes, factory letters, paperwork ,,and experts testimonials.
Added: I don't recognize the engravers mark on the bottom. Most likely an aftermarket engraving job as W didn't want contract or even the in-house custom shop engravers to mark their work. The latter allowed on special jobs/special occasions presentations sometimes, but as a general rule, no mark or signature. They'd sneak one in once in a while though!