US Defense solutions has at least 1 complete one. I'm sure probably more. 5329 mount pleasant north street, greenwood. At 37 and county line road in the strip mall behind the shell station. That's the place to go for all your AR15 parts and knowledge needsAny local gun stores with armorers or online vendors that sell a fully assembled A2 gas block front site base so that the only thing needed to be done for installation would be the gas tube and roll pin and the taper pins on the bottom?