Internals are key IMO. If you have Stainless solid rod grates, they can easily be cleaned up with a wire wheel and angle grinder. If you have burners that are in good shape, you can clean them up usually with the same wire cup brush and angle grinder. Most flavorizer bars you will come across are usually pretty rough and ceramic coated steel. They don't clean up well at all.
Otherwise, there are decent replacements on Amazon for all three in Stainless. Price varies with how deep you clean up the grill and parts that you replace. Market area is also a variable. Look on FB MP and CL and find some comparisons. If you finish one up, you could post pictures and get some more accurate feedback from the forum as well.