finding a barrel wont be a problem since any gunsmith worth his salt can have one fitted and headspaced. if a gunsmith has already looked over the rifle and determined the barrel is mostly shot out, a quick way to gain accuracy would be to rechamber the rifle to .223 and recut the crown. most barrels that are shot out have eroded throats (the transition area between the chamber and rifling) and crowns. cutting the chamber to .223, which is basically a lengthened .222, will cut away some of the throat that has been worn down. in my own experiance, the .222 isnt a caliber that burns barrels quickly so if i had to guess maybe you have excessive copper or fouling in your barrel. i have found that sometimes completely taking a rifle apart, cleaning it and putting it back together with everything tightened down can fix most reliablity or accuracy issues. be sure to check your scope mounts and scope (yes take the scope out the rings) and clean all the possible dirt out. take a straight edge and try to find any warpage in your stock. eliminate the variables before a expensive visit to a gunsmith.