Check with Matt or Martin at MAS Gunworks in Moore. They've usually got a bunch in stock. Matts the one I bug all the time for my Magpul and YHM stuff. Speaking of which I need to give Matt a call tomorrow.
I've seen it here and there, but no one seems to be a stocking dealer in the Tulsa area. For that matter, it is difficult to find any decent AR goodies at all. UTG, CAA, NCStar, Tapco, etc is abundant while what I would consider the standard quality stuff like KAC, Larue, Magpul, Daniel Defense, Aimpoint, etc is virtually nonexistent. I guess 'cheap' sells better around here.