No rebuild kit. I pulled off the starter, opened it up and cleaned it out. Starters haven't changed much since the 1940s, and if you've ever worked on/cleaned an old Lionel toy train locomotive, you can handle a starter. There's not much to rebuild if you did, the only wear parts are the brushes and commutator. If the commutator is toast, might as well get a new starter. Then the gears in the planetary gearbox. I cleaned those, too, and greased.

As far as brushes go, to me it looked like you'd have to replace the entire brush carrier assembly. Looks like they can be found online.

 

So a final follow up:

Starter died a quick death out in the boonies this weekend. Thank the lord for stick shifts and push starts.

I will post photos for reference, but turns out the grooved commutator and brushes only lasted 5 days.

 

Go to widautoparts1993 on eBuy.
$50 for a rebuilt on OE core with one year warranty.
I put one in. Very nice,and I like that it's on OE starter.