Polish gear is complicated. The Polish army starts with it's own gear, then after the fall of Poland, they were re-equipped by the French, then by the British. Other Polish units were equipped by the Russians and during the Warsaw uprising there is a mix of civilian gear and captured German gear.
http://www.warhistoryonline.com/war-articles/20-images-wwii-uniforms.html This may help
Russian is a bit easier http://www.ww2airsoft.org.uk/ussr-rkka-summer/
If you ask around on ww2airsoft.org.uk, there are people who do Russian and even Polish gear.