Bummer on the bent valves. But that would cause it to misfire on those cylinders, that's for sure.
Check out the Truck Parts For Sale and the Truck Parts Wanted forums. There's a 2235 motor with 3 speed trans for sale in there right now. I just glanced at it, so I don't know where it's located, but that's a good starting point.
I don't have any motors for sale at the moment...and all of my stuff would be newer that your 53...otherwise I'd be happy if I could help out a fellow Bolter. All I have as spares right now is a 406 V8 in a basket and a seized-up 454.
Good luck with it.
