I just found out that Rosegal has a bunch of false nail sets under their beauty section...
The 24 packs start from roughly $2 and don't forget that Rosegal is offering free worldwide shipping on all orders!
I have checked Boohoo, ASOS and Priceline in the hope of finding cheaper sets, but as you would have guessed $2 delivered is a bargain hard to beat. Boohoo stocks sets for $6, ASOS has them starting at $10, meanwhile at Priceline you're looking at paying a minimum of around $8.50 for a pack of 24 false nails. And delivery comes on top of all of these prices.
I have ordered from Rosegal before and I'm pretty happy with them - the tees I have bought previously are ok quality for the price, but delivery took a bit long. That's the "price" of free shipping, however, if you don't want to wait you can pay a bit extra for shipping and get your order delivered a lot faster.