Amazon offers Prime members the Hori Retro Mario GamePad Protector and Stylus Set for Nintendo Wii U for $7.47 $8.37 with free shipping. (Non-members can spend $35 to qualify for free shipping; otherwise, shipping costs $4.98.) That's the lowest total price we could find by $12. This case protects both the front and back while allowing access to all functions, including while charging.