I have no idea if I am in the right place, but here goes. I recently acquired a Bushmaster XM 15 Pre Patrolman Pistol (XM 15 E2s pistol), new unfired in the box. It resembles an AR 15, but has a 7" barrel and no stock, but rather a stublike attachment you hold under your arm. I can find no information on the web about this weapon. Does anyone know what I have? Value? Use?