You really needed to copy those marks off for us. is it a rifle, or a shotgun? are the marks in english, or foreign language?
Here is what I can observe. it looks very strongly european. those are roe deer, unless I'm mistaken. The sling attached to the barrels is a uniquely european thing.
The very long sideplates and the short, rounded hammer are unusuall. It appears to have rifle sights.
The fit of those side plates is unbelievable. the engraving is quite nice; the checkering on the action lever and the engraved screw head are very nice touches. the checkering is nice.
I'm going to take a guess at Germany or balkan area, turn of the century, smokeless, probably a rimmed 8 mm cartridge, and that was a fine piece in its time. It was used, but cared for, and owned by real wealth and influence. This was something that went out on the hunt when the burgomeister went to deer camp. it wasnt' drug out by the guy who cut firewood and poached deer for a living.
I'd love to see better pictures, and I'm really looking forward to the experts weiging in.