I bought em from PORC off Pirate and had a reputable shop set them up. I'm letting the shop use their own brew this time.
See if you can hit them up on the warranty:
Package deal includes front and rear 79-85 Toyota 4cyl or 79-94 8" rear 4.11,4.56,4.88 or 5.29 Porc Off Road products ring & pinions with complete master install kits. THESE ARE NOT CHEAP CHINA MADE GEARS LIKE OTHER VENDOR'S OFFER. THESE ARE THE HIGHEST QUALITY GEARS OFFERED ON THE MARKET TODAY. WE ARE SO SURE OF THE QUALITY OF OUR GEARS WE BACK THEM UP WITH A LIFETIME WARRENTY AGAINST MANUFACTURED DEFECT'S. MASTER INSTALL KIT'S HAVE ALL KOYO BEARINGS & NATIONAL SEALS.