I have designed an accessory mount for the E-Z Ray Gun (with stock). Print it at 100% infill/density.

To mount it, take the Second Mount and mount it to the wall with push pins. Then grab the E-Z Ray Gun with stock attached and the E-Z Ray Gun mount. First, put the Ray Gun up to the mount while still holding it, where the grip meets the body. Then use push pins to mount the E-Z Ray Gun Mount under the stock, near the butt of the stock. When you're finished, put the Ray Gun on the Mount, pushed up flush against the wall.