In my experience with large re-built MV induction motors, you're better off buying a new one. Yes, I know they are much more expensive but, I rarely have seen a re-built MV motor last nearly as long as a new one. They just don't hold up. Not sure why. Not sure if its a motor shop process issue or what. I've been to many motor shops to watch or participate in the process but, when the motor is placed into service they never seem to last as long as they should.
My 2 cents.