As near as I can tell, there was almost no structural modifications done here:
The artist obviously painted the toy, but if you look at the original (the Nerf N-Strike Maverick Blaster) closely there’s actually a lot of steampunk-friendly detail there already. Even the nameplate is actually in the original; the paint job merely makes it obvious. It makes you wonder why Nerf didn’t simply produce this beauty in brass and brown rather than yellow and gunmetal in the first place…
It dosen’t make me wonder, so police don’t ever mistake it for a real gun. Remember the accidental shootings of kids in the 90s?
Point taken.