(This venue is closed.) The price is right.
That's not merely a suggestion, that's the actual retail price, and it's hard to go very wrong unless you buy so much that you dip into the folding money. Ferrara Pan brand Hot Tamales, Boston Baked Beans, and Red Hots set me back just 25 cents each, though over visits two years apart, the boxes shrank from 1.3 oz. to just under an ounce.
Then again, on a more recent visit, a box of Dots and a coconut Long Boy required the outlay of just 25 cents total; you might scrape together that much by jiggling coin returns (which were much easier to jiggle in 2010, the date of that more recent visit). For the extremely thrift-minded, the shop sells Starburst loosies, too.
Sweet Banana itself is less than polished, even a little dingy, but I've always received a friendly send-off.
Sweet Banana Candy Store
112 Ninth Ave. (17th-18th Sts.), Manhattan
212-255-0673