I bought a recon starter,
TBH all looks new -
I had an oppo who used to work for an autoelectrical reman unit.
They basically stripped and rebuilt every unit from parts-
it was too time consuming to measure bearings, cases armatures etc.
All parts were stripped to component level -
Inspected for replacement suitability
bearings removed and replaced --- (huge mark up on bearings from dealers!!!)
Cases washed and steam cleaned / shot blasted / painted as required
Commutators / windings solenoids etc , checked for electrical ok ness
- generally junked though and then rewound.
New brushes & springs fitted
reassembeld & tested.
I only know of one place that rebuilds rotating auto stuff at the moment, the other, a big company closed its walk in repair counter a few years ago