I've just discovered that if you get Zvezda's reliatively new Soviet Cossacks, and paint the cloaks and gymnastiorkas (tunics) grey, you get WWI Kuban-Terek cossacks! Also, I hear that this winter, Zvezda will be releasing WWI Russian and German infantry in 1:72. And maybe they will scale them up to 1:35. But to fill in the gap for the time being, for 1:72 collectors, if you need some more russian infantry becuase of the exeptional late war uniforms of the Strelets sets, or the lack of poses from the HaT set, to make WWI Russian infantry, all you need to do, is trim off the backpacks from 'Prussian Reserve Infantry' figures (Actually, a Napoleonic set!), and paint them in the colours of WWI Russians, you get the perfect replica (Excluding the Officer). Oh, and also, soon (Hopefully) Caesar Miniatures have been making Russo-Japanese war figures, and the upcoming Russians in those will be perfect for WWI, provided, once again, that they are painted correctly. Thats all!
