I have no idea, but I'm not sure they would consciously ape the hated Russians (or the Germans, for that matter). Though of course that all depends on the circumstances that led to our hypothetically independent Poland. If the Russians had lobbied for it at the end of the Napoleonic Wars (so as to create a buffer) the Poles might well be more well-disposed to Russian fashions (with the same applying if it had been a Prussian idea).
Anyway, perhaps you could draw some inspiration from the Polish Legions of the Austro-Hungarian army during the Great War.
Edit: Hang on a minute, I didn't know Dick Strawbridge was in the Polish Legions...
