Sweet actually makes a winter line. Clothing and helmets. I believe the helmet shells are the same as the kayak helmets, but the liners are different due to the different impact characteristics in kayaking vs skiing. But I could be remembering wrong.
Also IIRC that helmet shell, by the way, is an interesting micro-laminated polypropylene. Supposedly bullet proof. Although one of my kids cracked the brim due to a deck impact when hucking the 2nd ever Hail Mary off Maruia Falls. His nose met a similar fate... (edit: looking at the site, it seems that shell is not in the helmet snow line)
In general, Sweet's winter stuff is not distributed in the U.S. Bummer, 'cause they make great stuff.