If the hub was not leaking oil, you can get by with old seals.
If the bearings were not worn out (they incredibly rarely are), you don't have to replace the bearings.
I don't remember when was the last time I replaced either - it was definitely more than 200 thousand combined Rover miles ago, and it was not necessary (a might-as-well-do-maintenance thing).
Replacing the rotor is an easy, even if more involved than usual, job.