I once accidentally found a website that has all sorts of soviet uniforms, gear, helmets, belts. gloves and everything but I forgot the name
if it helps I was searching for airsoft soviet uniforms.
EDIT: altough I doubt they have Navy stuff, here it is
http://www.sovietarmystuff.com/
EDIT1: you're in luck, check the Uniforms section and you might find what you're looking for