I have had a NAPA rebuilt alt in my car for years with no problems. But I am never more than 20 miles away from a NAPA store if it needs replacement. I would also guess new ones are really cheap, unless you need a high amp alternator or a single wire one. The reasons you might need a high amp alternator is if you have halogen headlights or an electric radiator fan. Both of those are large power hogs. A amplifier for your radio typically does not take that much power. A lot of people think it does, but that is not reality. So a standard 60 amp alternator could work fine, I have used it for 30 years, even with AC, high power amplifiers, and halogen headlights.
A solid state regulator is a good idea at the same time. It is also a good idea to insure all the wires and connectors are secure and clean. Send your engine harness to Midlife and have him check it over, that will remove all doubt.
Get on the road, summer is coming!