I have been looking for a replacement bumper myself. I think they run around $350 "new" from Isuzu and like wintermute said, you used to be able to get them from RockAuto and I've seen them here too: http://shop.iautobodyparts.com/isuzu...0-parts-0.html but I think they are out of stock also.
I have been talking to a local 4x4 shop here and they said that they can fab up a new one, with end caps and powder coated for (if I remember right) $250. They also said that they would be happy to fab a few up for others on the site here and would ship them where ever they needed to go. They said that they could just bend up the tube, and cap it so that someone could weld it to their stock bumper mounts for $150. I haven't talked to them in a while, but I need to get my bumper done for sure, so if others are interested I can get some firm pricing done.
OH, and the cladding looks great.
"The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong, it usually turns out to be impossible to get at or repair."
-Douglas Adams, Mostly Harmless