Captain Proton's Ray Gun

The kids and I are big Star Trek fans (well, the 5-year-old is just a fan, not a big fan, as yet), and my son wanted to have Captain Proton's Ray Gun. Captain Proton is a cheesy character in a fictional series of 1950s movies in Star Trek Voyager. So, I guess, he's a fictional fictional character. I found some photos of a prop, traced the images in Inkscape, exported to OpenSCAD, and made 3D printable files, which are here. I printed it (it prints in two halves that join together), but we have yet to paint it (may not paint it right away, as in silver and gray it will look too much like a real gun at a distance to use outside the house).