Weeeelll, if the $ are burning a hole in your pocket, Hans Vang will sell you a completely tricked-out 870 or 870 PM. It lacks (maybe?) only a light. Check out
http://www.vangcomp.com for details. There are arguments (Dave, this is your opening <g> ) for spending less on hardware and more on ammo and training, but if you want to spend money on hardware, Hans is YTM.