Man, you want me to do all the searching for you

?
The difference between the ST and the 7/8/8.5 is the pinion gear teeth count. Like I said in my previous post, the hyper ST has 43T in the crown gear (which is the same as the 7/8/8.5) but the pinion only has 10T compared to the 13T on the 7/8/8.5 models' pinion. The diff ratio will be 4.3:1 (for a 43T crown gear divided by 10T pinion) for the Hyper ST while the Hyper 7/8/8.5 is 3.3:1 (43T crown gear divided by 13T pinion).
As for the 8 spyders, CFalco of RC-holics on ebay used to sell them. Here's a link to his ebay store. You can also email him and find out if he has some.
http://stores.ebay.com/RC-HOLICS/1-8...ERENTIALS.html
Just to add more confusion to you

, I'm also using kyosho 6 spyders since they are cheap here in Japan.