I bought this a while back so that when visiting client sites I could plug my Surface Pro 6 into the various usb-c hubs that are used on hot desks.
I don't really need it anymore so time for a new home! I seem to remember paying around $200 for it a couple of years ago so PM me an offer if you are interested.
The model number seems to be HVU-00005 and I got it from PB Tech, although it's very hard to find details about it online now cause it was reserved for Commercial and Education customers.
I did find that on some docks I could use the screens and keyboard etc but my Surface would not charge, which was okay but wasn't ideal so you need to bear this in mind.