On the way to the club classic today and noticed smoke from left trailer wheel after about 5 minutes down the road. Neighbor looked at trailer after I took the wheel off and says I need the hub, brakes, spindle and bearings (front and back). I have never done this and how do I know what (size, etc) to get? Can you buy the entire assembly?

It is a 1997 Stratos trailer, single axle.
21'