starter. I'm kind of glad nobody could do it the same day since I would have otherwise never attempted it myself. I figured I'd need to replace bearings and the brushes, but everything checked out fine on mine, despite it not starting at all. A quick cleaning/sanding of the brushes and everything else, and all was well.
But it's one of those things in the back of my head that I'm expecting to have to revisit sooner than later, so knowing what is involved in a legit rebuild is good to know.