They make plenty of dremel buffing 'disks', but I'd try to find the 'tip'....they look like a Q-tip mounted to a metal rod. It's hard for me to find cakes of true jeweler's rouge these days, that you could buy in specific grits or at least by coarse, medium, or fine. If you can find them, start with red and finish with white. The paste stuff that you find these days usually doesn't say a grit on it. Instead, it's rated for material/use. I use the tubes that say for metal scratch removal/heavy polishing, to start with. Next I move to the next finest/softest they offer for buffing out my polish marks from the other. I am not a finish or restoration expert, but there are some tricks I've gotten from some who are very good at it. IF you should get into that trigger radius angle by accident, you will need to make a small sanding block and fine paper and sharpen the edge up anywhere you may accidentally round it some....just to keep it from showing as being polished. if it's bead blasted (as it appears), tape it off to start with in that area, and don't touch it, unless you want to have it blasted all over again....no way I know of to match bead blasting.
Here's a thought: Let the ducks work and decoy.