Since it is aluminum, an alternative approach would be to wet sand the receiver with fine-grit emory cloth and bring it to a polished stainless-like finish. It's not going to rust, obviously, and if you do get a scratch on it (no more likely than if you paint it, or if it's anodized), then nothing is easier to touch-up. Then touch-up the pins, trigger guard, etc, with black paint for contrast. Not saying it's what I would do (but I might)...and you'd have to like the look, but there are some "marine" models that look similar.