I'd say that was a hot round. I can't help you on the receiver question but would think that if it can be built up and worked back into shape, you will at that time have to re-Parkerize at least the receiver. Don't take what you think is the easier way and try to do the barreled receiver because you will have to remove the gas piston. Sometimes you will cross-thread the piston nut on reassembly and crack the thin gas block at which point your carbine is toast. And removing the barrel is no fun either because it requires specialized equipment to avoid twisting/breaking the receiver. And make sure you check that receiver for deformation like Manteo said before spending a nickel on repairs. I'm sorry to say I think you are in serious trouble with that carbine.