CV Joint advice sought

I think i might have a CV joint problem.

I started getting a vibration at 60mph, which over say 50 miles turned into a really nasty vibration on over run or when slowing down.

Does this sound likely that it might be a cv joint and more to the point where can i get one (or maybe 2).

This evening I have googled the part but can only find CV’s for S1 exiges and elises, therefore can anyone assist in pointing me in the direction of a motor factor that might have them for an S2 or is the cv the same as the S1 ie rover derived?

Maybe the inner tripode is more likley at fault with that symptom ?

You’ve checked that all of your wheels are torqued properly??

What is an inner tripode?

The rear wheels are torqued properly, I checked them this evening and had only driven the car 50 miles or so from when i had the geo done and, wait or it, the O/S driveshaft regreased!!

Could this be linked?