If that is what the OP is referrring to then i think it would be near impossible to figure out the exact model of the helmet as there is no indication to which brand it is.
there really arent that many ski helmet companies so id say just find out if he has a helmet sponsor and go from there, or just check out the top companies' sites, i imagine youll find out which one it is pretty quickly
I know that last one is a Giro Shiv, which they don't make anymore. But I would check out the Giro Ledge if you're looking for the most similar model that's currently offered.