The SSGTS comes with an adapter for 901/510 connection. I can't recall to be sure but belive you may need a different adapter for 801 if you are thinking of trying them. The SSGTS is pretty much plug and play, takes most mod batteries and the telescope just adjusts to accommodate. When people talk about parts it is because you can buy a SSGG Stealth and upgrade to a TS with some extra parts. That can get expensive as some of the parts are tough to track down. There is also an optional upgrade kit for the Ody.
The fun thing about the GGTS is that it's versatile and the creator, Imeo, is regularly "outdoing" himself by creating new inventions to enhance the GG experience. It's worth the patience and the wait as they are amazing and last a lifetime.
Again, best of luck w/ the search. Hopefully some will come in stock soon.