Rather than reinvent the wheel why not use the same wording as on the Shoretrooper CRL?
E-11B Blaster
For 501st approval:
Based on a real or replica Sterling sub-machine gun, scratch-built, or a modified commercial toy Stormtrooper blaster.
Tactical flashlight (Surefire scout M300 or replica) mounted on right side of barrel.
Magazine shall be full length.