If you don't want to make scrapers, Brownell's sells them. They have 3 that I know of that are useful, and have a different profile on each end. They are red, blue, and green. Last I saw, about $15 each.
Some folks break a bottle up in a paper bag and use the random shapes as scrapers. Of course, this only works for scrapers intended for scraping wood. When it gets dull, throw it away. (Put masking tape on the edge that you will hold to protect yourself.)
I actually find that early efforts in gun making are worth keeping around, warts and all. Not just as a trophy to show yourself how far you've come, but in retaining them with the mistakes in them so you are reminded NOT to make the same mistakes again. Also to remind yourself in looking at it what your mental thinking process was that led you to make it in the first place. If you try to do it ALL in one gun, ---particularly your first (unique architecture, carving, engraving, wire and metal inlays etc.) you won't have far to go to find a gun in the rack to look at to find one with all your mistakes in it. Treat it as your "learning gun" and it will be valuable to you as a builder that way.
ApprenticeBuilder;
That last photo of your carving is fascinating. It appears that the outlines of your figure is positive to the wood, and the interior of the figures goes below the regular surface plane. Very clever and ingenious way to gain more depth without a lot of relief in actual height. That's the essence of good low relief carving. Make it LOOK high without actually BEING high. Very difficult to do.