A UPC is required per release. You are welcome to use your own UPC if you have one, otherwise Record Union can generate one for $10 – just check the box for "I don't have a code, please generate one for me" when creating your release.

An ISRC is required for each track. You are welcome to use your own ISRCs if you have them already, otherwise Record Union will generate them for free (just leave the field for ISRC blank).