You can look at the Rigd Ultraswing if you want a nice hitch mounted swing out tire carrier instead of a full on bumper. I don’t have personal experience with them but most reviews speak very favorably.
Looks like Don Thuren is fulfilling the dreams of a few folks looking for a rear bumper, with the possibility of "attachments" and a "swing out". Will be interesting to see what becomes of this, there is more info up on his web pages. Hopefully this will be as awesome as his front bumper! (y)
Obviously bumping an old thread but there are a couple of rear bumper options for Power Wagons now.
AEV rear 2500 bumpers work, no swing out though.
Chassis Unlimited has a couple of models, one being a high clearance design that cuts a portion of the rear fenders to gain a few inches.
SOB Fabrication in Santa Fe NM makes custom bumpers for the PW and has a high clearance option as well.