In fact, the Classic Super Famicom Controller for Wii is functionally identical to the Club Nintendo version. It plugs into your Wii Remote and lets you play Virtual Console games (or anything else that supports Classic Controller use and doesn't require analog sticks) with a controller designed to replicate the SNES pad. It even has the colorful face buttons of the Japanese controller.
Right now seems like a questionable time to buy a Wii accessory, but you'd already be using it to play old games. The impending obsolescence of the Wii isn't necessarily a deal breaker. Besides, the Wii U uses Wii Remotes; a Classic Controller might come in handy with that as well.