I'm looking for a Rock River M4 setup (AR1291; can never remember the exact model), flattop, preferably with a quad-rail already installed,and M4 style barrel. Surefire would be preferable, but durable would suffice. I DEFINITELY don't want the integral upper receiver rear sight, either in the A2 style, or the RRA-specific rear sight. So, I would be very appreciative of any suggestions as to the cheapest places anyone has found for an AR of this type. The going rate I've seen seems to be around 1000, give or take. Any info would be much appreciated. Thanks in advance.