In series 2, there are SNES buttons (light purple, dark purple), Super Famicom buttons (red, yellow, blue,green), N64 control stick, N64 buttons, GameCube c-stick, and GameCube buttons. They're are no shoulder buttons.
You can buy them at any Nintendo store in Japan. 600 yen per, but it's a gachapon (random capsule) so no guarantee to get what you want. I got 5/6 in the first 10 pulls, but did another 10 to get the GameCube buttons.
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