Years ago, I replaced the Mando alternator in a Bobcat with an internally regulated Delco. The boss was very happy that day.
As to your "use your local rebuild shop" comments, for a lot of people it's just not possible. My wife owns a 1938 Graham Bradley tractor. (You'll have to Google Image that one) I took the generator in to the nearest shop to be rebuilt. My nearest shop is a full 75 minutes away, one way. So you drop it off, and then go home. Pick it back up, and then go home. That's five hours of driving for that. Plus, he's not open on Saturday, so you'll have to take off work to get business done with him. When you walk in, he always has his arms crossed in the defensive mode and is in a pizzy mood. (Despite buying a dozen donuts for him and his workers)
The previous time I had generator work done was on an Oliver 550 tractor. (Google that one also) He put on the wrong regulator and I had to make another trip back. He didn't use the regulator that the specs called for, but instead used one "that will work". Well, it worked on his test machine, but didn't work with the factory wiring harness.
If you've got a local starter/generator man, by all means use him. Despite living in an agricultural area, they are almost nonexistent here.