Jerry,
My rear hubs and differential were rebuilt by TRF. No complaints whatsoever. Spensive, but worth it. They even drilled and tapped the diff so I could change the lubricant.
Remember to check where the hubs bolt into the aluminum trailing arm. Triumph did a poor job of designing these in that you have fine-thread bolts going into soft aluminum. Not a good combination. Several of mine had been JBWelded in by the SPO. I tapped em all and HeliCoiled each bolt nice and securely.
Bill