Here's a picture of my Wii Speak and other parts--I modified the accessory to work with a real headset! : r/WiiHacks
Wholesale WII U Controller PRO Wireless headset for WII U Console-Wireless Bluetooth+Anti-skid Stripe+Color Key+Black Transparent Shell from China | TVC-Mall.com
Turtle Beach Headsets Coming Soon for Wii U and 3DS - News - Nintendo World Report
Official Nintendo Wii U Stereo Headset, Black, Used. With Microphone PSWII20 | eBay
Tritton Kunai Stereo Headset (Nintendo 3DS, Wii U) White
This One Feature Could Make PlayStation VR the Wii of Virtual Reality - Variety
Turtle Beach Wii U Official Headsets Announced - News - Nintendo World Report