A bad rod bearing is not a big deal. Any mechanic can deal with that. I've done this job in 2 hours taking my darn sweet time. However, the condition of the bad bearing will indicate what caused the damage. If it is severe enough then the possibility that the crank was damaged is more than likely. *(If it is a turbo crank remember that these cranks are heavy duty. They can take a lot of severe punishment and still not need to be replaced. Unfortunatley, it cannot be machined). The crank would still have to be checked. This check falls upon the hands of a machinist. (A mechanic can do this if he knows about tolerances and has an understanding on how to read and use a micrometer).
Obvious checks would be a scored or scratched surface on the crank. If it is a turbo crank then it is not salvagable! Turbo cranks are roll filleted on the rod bearing surface and main bearing surface. Meaning that it cannot be turned, (cut).
If a new crank is needed then one would then need a 'crank kit'. Aproximate cost is ball park $300.00. (This does not include labor). It is doubtful that the replacement crank will be a turbo crank since they are very rare. The machinist would probably then use a standard 3.8 crank.