The one I brought, it’s amazon U.K.
I’ve only had it a few days so I can’t speak much about it, but it works exactly as it should and came with the stand with adhesive on the bottom which was useful.
I have this OriGlam Wii Sensor Bar USB Replacement - Works with Wii / Wii U - Best SensorBar for Windows Xp, Vista, 7, 8 which was said to work just fine in the comments. Though I connect it to my computer and nothing happens. Windows doesn't even give the jingle to let me know it's connected. Doesn't seem to help anything.
EDIT: I have Googled many times how to get the sensor bar to connect to Dolphin/Windows but the typical response seems to be "it just works".