If the
stator was rebuilt, that is a very good price.
Drying out or rewinding/repotting the stator is by far the most expensive repair one can do on an LDU; usually, it's not attempted because a replacement stator (and the gearcase half it's glued into) can be procured for less cost than rebuilding a damaged stator. I'm not aware of anyone doing stator rebuild in the USA. One firm in Arizona has a process that can dry out and reestablish isolation resistance of a soaked stator, but it's not cheap.
If the rotor can be extracted from the drive unit without splitting the gearcase -- I was able to do that on mine, with the help of a few bespoke
tools aids I made for the job -- then replacing the rotor bearings isn't too difficult or expensive. But if the the rotor has been subjected to coolant for much time, the only way to remove the rotor from the gearcase is to disassemble the gearcase, and the labor goes way up.
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IDK the timeframe when Tesla switched the rotor bearings from steel to hybrid ceramic, but prior to that time the rotor bearings can wear quite quickly from stray induced currents in the rotor, with the ball bearings serving as a ground path. The early units used a sort of whisker brush arrangement (Aegis ring) that was supposed to provide a ground path, but it didn't work. You can have one or both failing rotor bearings and have that milling noise, and not have a leaking rotor seal -- for a while.