When I see new alternator parts for sale now, most are WAI / Transpo made you know where. Quality could be anywhere.
Maybe some rebuilders have a few other sources. But at least one that can rewind has more options, and almost certainly has experience with what will work out in the long run.
There’s an older guy here that still does. He’s a great rebuilder and has rebuilt many an electric item for me, motors, alternators etc. trust the dude with even the rarest of parts. He does rewinding too.
There is a catch though, dude is a bad alcoholic. Not in a mean way or anything, just drinks a ton and doesn’t know when to stop. He’s been arrested more times than I can count for DUI. So he’s in jail a lot. But he’s stopped driving after they told him if he’s caught again, it’s a 20 year sentence