Trail Tough has some of the highest priced tcase gears out there. From what I have read, the quality of their's is really no better than the cheaper ones.
Trail-gear.com and lowrangeoffroad.com have 6.5 tcase gears with a lifetime warranty. Trail Tough gears only have a 1 year warranty, along with being more expensive.
You could also look for some used 4.16, 4.9, 5.1, 6.4, or 6.5 tcase gears.