It wouldn't cost that much from where you are I wouldn't think.No matter what you are gonna want to get the engine balanced.The fact that it wasn't would make me look really hard at the rest of it for quality issues.Having 8 bushings put in the small ends is not that expensive and in your case it would be a win win situation.As it stands right now you have the potential to have a very low compresion dog on your hands

You may spend some money on your heads though