Yes, but good luck finding somebody who owns one. The problem with owning one as a civilian is that you'd have to pay a $200 transfer tax to the BATFE for every grenade you purchased. Most "M203"s...
HEDP (High Explosive Dual Purpose), High Explosive, Star Parachute White, Star Cluster White, Ground Marker- Red - Green - or Yellow, Practice, Tactical CS Gas, Shotgun.