Bundled Party Balloons

The Clothier only lists his party wardrobe while a party is actually running, so it is easy to play for a hundred hours and never see this on his shelf. If you want the whole set of party cosmetics, force the event with a Party Center and buy everything in one sitting rather than waiting for a party to fire on its own.

Nothing about it can be reforged, so there is no reason to keep it out of a social slot where it would cost you a real accessory.