I always buy my Toploader kits from David Kee but getting parts for the T-10 is a different story. It seems to me that different retailers are all selling the same parts. I rebuilt several T-10's a few years ago and I bought my kits from- (The Gear Box Transmissions Inc). Besides the rebuild kit I also ordered a cluster pin, reverse idler shaft, Torque Lock Slider sleeves and a thrust bearing. These additional parts are not included in any rebuild kits I have seen and I would consider them a must have when doing a rebuild on the T-10. I buy my Torque Lock Sliders sleeves on eBay from- (superior.auto.parts) because the cost is a lot cheaper. If you are rebuilding a 1966 transmission then you won't need the thrust bearing. The 1966 transmission is a one year only version that was based on a AMC transmission design and is completely different than the 1965 and older transmissions and it also requires a completely different rebuild kit.