Replacing bumper wtih tow hitch on a 2005

I finally found a 2005 double cab Tundra with just 127,000 miles and bought it from a little old lady in far NW Montana. It's in great shape. But the bumper is very bent, so that the tailgate rubbed when hauling plywood. I found a bumper at a junkyard and bought it. Come to find out my bumper is welded to the tow hitch, and is not the same as the one I bought, which is a much smaller simpler deal. On my existing bumper, it appears the bracket is damaged/bent, in addition to the chrome part. Do I need to buy a whole new tow hitch/bumper? Can I use an aftermarket tow hitch and the salvage the chrome part of the bumper I already bought? Advice please!

The bumper in the grass is the new one, with a pretty simple three-hole bolt attachment. The underbody pic shows that my bumper is welded to a massive tow hitch, and appears that cannot be replaced with the one in the grass

 

Pictures would be very helpful to those trying to weigh in and help...