Another option if you are concerned about seal wear, is to just use hub savers. They are a very thin hard stainless steel sleeve that presses on to the wear area. They are meant to repair hubs with deep seal grooves worn in them. Since you used standard trailer bearings, I'm sure you can find them. They also use the same type of system to repair harmonic balancers on engines with seal grooves worn in them. They are thin enough that you can use the same size seal, it will just have a little more tension on the slightly larger diameter shaft.
Long arc, short arc, heliarc and in-the-dark!