Welcome to AF.
You are better off just getting another complete hub assembly and not worry about specific internal parts since most are integral. I've had the best luck out of the AC Delco replacement hubs. Also, keep in mind there are two axle nut torque figures depending on the type axle nut used. So the right torque spec has to be used or the bearings will prematurely fail.
On the brake issue inner rotor wear is some what normal but check the operation of the caliper and make sure the old grease is cleaned off and new added on the caliper sliding pins.