Hopefully this is in the right place.

Found this today, local find. I do know that the owner of the shop where I found it was quite a collector back in the day, especially of Mauser Broomhandles, but he wasn’t there to tell me anything about it.

I can’t find any info or a picture of another one, or figure out what the No: 277 means?

Was it a wall or doorbell plaque, is it off a box or a heavy gun?

What would be the approximate age of such a plaque?

WWI era?

Any info appreciated, thx.

Click to enlarge the picture