In shopping, look for: recommendations from several racers of Mopar engines, a power hone, deck plates, line hone, and such so that the machine work is great. Which usually means better than OEM production, when it's all said and done. Understand, too, that great machines in an old building, run by somebody who knows what they are doing can be better than a newer building with equivalent machines run by "employees". Talk and watch how they do things, though. Ask questions, too. Ask respectful questions that a newbie might ask, too. How they answer them and in what manner can speak volumes, by observation. Might take a good friend with you in these shopping expeditions, too, for a second opinion/thoughts.
Once the machine work is done, then request parts of at least OEM quality. Do not need "race parts" unless you are going to seriously drag race the motor. Request a Cloyes roller timing chain, too. Ask about the gasket sets (usually Fel-Pro or equivalent), too. Plus type of bearings.
Be careful, too, about the model year of your block if you are going to build another block instead. Verify the date codes and such. In some of the later model blocks, the accessory drives were different with some having bracket mounting holes not where they need to be for the particular model year of brackets and such. Make sure everything matches on both blocks!!!
Just some thoughts and observations,
CBODY67