forget buying boots online. rotten idea.
I don't know what yer girl is like, but more than half of the appeal of the clothes is going to be how she looks in them, again, not too easy to buy online. Considering how different coat and pant fits are, a trip to a shop or 2 or 3 is a must, if only to find what brands and styles fit / look the best.
From my wife's personal experience, I'd say go with a shell jacket, and invest in layers, puffy's get a little warm, depending on season and where you board. We have to travel to board, so flexibility is a must.