If you can get it for three bucks, what does it matter if Junior is busting through the snaps on the crotch of that adorable onesie in less than six weeks? Gymboree, Baby Gap, Old Navy, Little Me--all those adult-priced labels that taunt proud new parents from store windows can be had guilt-free at this southwest Minneapolis consignment shop. There are teeny socks, buntings for every conceivable temperature variation, winter hats, sun hats, a whole roomful of clothes sized for toddlers and preschoolers--even a decent designer selection for Mom. Wares are chosen carefully, so if your treasures are in good shape when you're done with 'em, bring them back and consign them and spend the proceeds on yet more goodies. Hours are restricted, so you'll have to time your visit: Thursday and Friday 11:00 a.m. to 7:00 p.m.; Saturday and Sunday noon to 5:00 p.m.