They're called crop tops. You can generally find them anywhere because they're on trend. Try these stores; debs (debshops.com), forever 21, charlotte russe, delia's, wet seal, topshop, nasty gal, aeropostale, hollister, rue21, dots, body central. The list continues, but I'm sure any store you go to will have them. :)

Why don't you just buy it off that website? Its only $5

Try Ebay or Amazon, they always have tops like that.