If thrift store fail you, I would also check ebay. One can almost always find what they're looking for on ebay, as long as you look hard enough. I just did a quick search for "black white stripe sweater" and found a couple fairly close matches for $22 or less.
'Idiot's Lantern' Rose Tyler (Doctor Who)
Astrid (How to Train Your Dragon)
Tinkerbell (Peter Pan)
Reviving This Year:
Annabeth Chase (Percy Jackson)
Katniss Everdeen (Hunger Games)