N64 USB ADAPTER

Not sure if I'm suppost to post this in this section but anyway ... Ive been playing n64 Roms for a while and decided to try and find a usb adapter for n64 controller. Ive found 1 on eBay but i was wondering if theres a store that sells like dual usb adapter for n64 controller.

Like this:
http://www.play-asia.com/paOS-13-71-6m-49-en-70-3d9o.html
http://image1.play-asia.com/640/8q/pa.157164.1.jpg