Personally if the backlash/wear checks out on the ring and pinion, "within specs" just get the bearings and axles replaced, if the axles are even bad, almost sounds like you are being oversold, but you can never know til you see the parts your self. Back to the point. I would expect to pay around 500-700 for new bearings. I would keep shopping around til you find a reasonable shop.
Used you never know what you get, the ring and pinion might check out visually, but the bearings could be half gone, so I think new bearings are worth it, the only complicated part about cleaning the housing is the area next to the caps, there is a groove there that loves to slice your gloves and make you wake up at the feeling of a cut.
