Really Pickel, the MiG-3? Why? That was basically junk compared to the ME-109, and not a great aircraft, even in Russia's eyse, despite the cool MiG name, which had me interested enough to look that one up.
The Russian aircraft I have been wanting to get my hands on now for years is the YAK-9!
It was the first Russian fighter to shoot down an ME-262, not to mention the most mass-produced Soviet fighter of all time. It hit the ground in 1942, and had one of the longest histories of use by Russia in WWII...This plane was even used by North Korea in the Korean War...pretty solid prop fighter for its time. I think this might be the FW-190/P-51/Spitfire of Russia, no?
It is a MUST to have at least one Russian plane to display against all the USA, German, British, and Japanese stuff... I would definitely pay for the Yak-9!!! It is cool looking too.
Check out a picture here:
http://world-war-2.wikia.com/wiki/Yakovlev_Yak-9
The Polish PZL would be an excellent plane to have as well, despite absolutely hating the look of them. They were what the Polish Airfore was mainly made up of in 1939 when the slaughter began by the Germans. Having that displayed would really make it heavily appearant just how outclassed they were by the invaders, and how unfair the entire conflict was at the beginning.
I would buy either...not that I think anyone would make the PZL unfortunately. BUT THE YAK-9!?!?! OH MAN! That thing just looks great!