Well I'm not sure of the cutoff either, if I were in charge, I'd leave it, simply because they're all Gen IV.
But if they do, then DP, MT are bound to be cut, SW too, but GE is iffy. If GE is cut, we lose Claydol and Unown G, from my understanding 2 very crucial cards in some decks, Claydol because of its drawing power (although my understanding is Uxie is taking that role more and more) and Unown G is used to prevent effects such as Machamp's SF Take Out.
As for getting cards, I bought boosters, but I'm pretty sure that buying the cards on their own is the way to go.