Yeah I'd get something like a windpant. You can get them at nearly any sporting goods store locally, I'd imagine. It says you're in Sweden so I don't know what retailers specifically you'd want to check out.
All the major hockey brands, CCM, Bauer, RBK, etc. make hockey specific "warm up" pants. I don't think there is anything special about them from regular wind pants other than they have the the hockey branding. Here's a pair for example.
http://www.hockeygiant.com/bau12ltwupntsr.html
Those will be quite a bit cheaper than ref pants and ligther, which can have a little more heft to them.