I'm very early on the process of learning engraving, so take anything I say with a large grain of salt. More years of practice are needed...
The sketchup you provided is pleasing - at least I find it so! But if you choose to engrave it, I'd alter it a bit first.
Some of the backbone scrolls are not as smooth as they could be. Most obvious is the left-most large scroll, where from 8 o'clock to 12 o'clock the line is too close to the center of the scroll. It should extend out a little farther, to produce a smoother expanding spiral.
Also, sketch in a casual overall outline of the engraved area, as if it were a string stretched over the outside of the pattern. It could be perspective and cameras certainly can lie, but the overall pattern looks bent rather than symmetric, appearing high in the middle.
Anyway a slight bit of touch up here and there can clean it up a bit. But as I said, I like the general pattern!
Now I may be off on this - I certainly haven't studied enough originals! - but I like to see a continuity of style between the carving and the engraving. But I do know that a lot of originals had different skill/difficulty level work for carving and engraving. I'm not sure of the artistic continuity of this scroll pattern with the rest of the rifle.
I apologize for being way too critical - and possibly flat out wrong. If I had that pattern engraved on any rifle of mine, I'd be pleased!
Gerald