Andy,
I am in the process of acquiring all the T-90 parts now. Miniarm is the only way to go. The good news is that their stuff is top notch. Even if an injection kit comes out, I can't imagine the detail being better.
http://www.miniarm.com/miniarm/?miniarm=productsYou will need:
T-90A Turret m2004 - B35033 or T-90 Turret m1992, T-90S - B35031
T-90 m1992, T-90S, T-90A, T-90"Bichma" Conversion - B35032
T-90A, T-90S,T-90"Bichma" workable tracks - B35034
T-72 Late Wheel Set - B35005
Tamiya T-72M1
A set of Eduard Photoetch for the T-72 would not hurt.
There are several photos of T-90s with T-72 tracks but these are apparently demonstrator vehicles. Of course if you are going to build one of these, you just saved yourself $35 if you are willing to use the Tamiya tracks. You could also cheat and use the Tamiya eight-spoke hubs but I have yet to see a photo of a T-90 that did not have the six-spokes.
If the good news is that this stuff is well done, the bad news is that I have had no luck in finding any substantial discount. I even had a Russian friend contact Miniarm directly. No luck. The best pricing I have found in the US at this time is at Mission Models.
https://www.missionmodels.com/home.php?cat=378I have also seen some of the components on eBay but nothing currently. All with similar pricing. Anyway you slice it, if you are going to do a full-on T-90, it's a two-hundred buck kit. Hope you like T-90s a lot.
Cheers,
John
EDIT: Or you could just read Andy T.'s post above. Drrrr...