Shortly after Super Smash Bros. for Wii U's grand showing at this past E3, accessory maker Performance Designed Products unveiled a line of GameCube-esque Classic Contollers that could be used on Wii U and, by extension, the original Wii. Themed after Mario, Peach, and Yoshi, these pads went on sale for $24.99 around the launch of Smash. They must be hot sellers, as PDP is planning four more!
If you swing by Amazon, you'll notice listings for Donkey Kong, Link, Samus, and Wario pads, all scheduled to launch on March 1, 2015. Again, these are technically Classic Controllers, so although they ought to simulate the GameCube experience, they can also be used on games that don't offer GC pad support. Even if you do have GC controllers still lying about and want to use them in Smash Wii U, you might not be able to due to the shortage of GameCube adapters, making these solid alternatives.
If these pads don't suit your fancy, you can always try Hori's GC-like controllers, which look a little more authentic and come with turbo functions.
