Here is the updated version, blue is less saturated and darker, buttons are smaller and silver-like instead of bronze. I tried to remove the brown strap belt of the original skin as it doesnt match the original uniform. The strap belt is white, and there is already a model ingame with a white belt and a pouch attached. You can easily make the white epaulette i guess. Also i fixed the "black collar" around the neck, now it looks like a piece of clothes.
As i said, its not really high quality but if you want it, i can send you the textures and you'll do whatever you want with it hehe ! Anyways, that's how i think the polish lancers of the guard should look like.
Edit: Images removed because there are outdated, new ones further down the subject.