If you're on a budget, buy the bad ones, not the good ones, and pill em like there's no tomorrow! Sferik and Belle are both incredibly cheap and each get you 4 pills if furied (5 with Timber, if you're feeling ballsy!)
If you're going for a mission, just buy a cheap vortex deck.
Sah Brinak, Selma, Ahkab, Taham, Brampah, Archibald, Brianna, Sferik, Katan, Hawkins Noel, Bonnie Ld, Candice, Anton, Belle, Bublgmm. These are the ones I can think of that are + Pill cards.