Colt is offering a limited number of M203s in 37mm to the civilian market. Because it's 37mm, not 40mm, it's not an NFA item. Looks like price is going to be $2k. Expensive, not practical but it sure would be cool to have an M203 that says COLT for my M4A1!
http://taskandpurpose.com/colt-civil...ade-launchers/