War Thunder and World of Tanks have some of the largest selection of ww2 soviet tanks and AFVs but are there others too? I'm interested in the T-70, KV-1/2, BT-7, T-34-76, T-34-85, IS-2M, IS-3, SU-85, SU-100, SU-122, SU-152, ISU-122 and ISU-152.

I think Steel Fury Kharkov 1942 with the Steel Tank Add-On will get you most of what you listed with missions to boot. Try here:
http://stasf2008.ephpbb.com/
Cheers

Does Panzer Elite Special Edition have any mods that add these vehicles?

The Ostpak will add most of what you are looking for Panzer Elite

As mentioned Steel Fury also has all the models you want.