I just checked what's included in the Denso reman alternator ($130).

1.Bearing 100% tested to OEM specifications and repacked with OEM grade lubricant.
2.Stator Insulation tested to 600 volts.
3.Rotor Performance and insulation tested to 600 volts.
4.Housing Re-tapped to OEM specifications and damage-checked for heat warping, corrosion, or improper surface alignment.
5.Hardware 100% stripped and replated.
6.Rectifier Performance tested to 300 volts.
7.Voltage Regulator 100% voltage tested to OEM specification.
8.Slip Ring re-machined to an average of 8 microns (20 micron run-out maximum).

It appears the rectifier/volt regulator is just tested, not replaced. They also state the bearing is just repacked, not sure how they'd do that as it is a sealed unit. One bearing is referred to so maybe only the front is looked at.

Just a reference in that I'm further ahead on the $$ game.