Please don't post personal information in any forum thread. Your email address has been removed. This is for your own safety and protection, and also ours.
Furthermore, being a sub-contractor and handyman, I often run into circumstances where I find hardware on some oddball thing that would work well for something in the field, on a house, apartment or other job, but can't find it even through the company that sells the item it is on. Good luck with that. Half the time the component is manufactured SPECIFICALLY for that item, and that company, alone, and the other half they simply couldn't care less to tell you who they got it through.
Very unlikely you will get any information about that hinge through Microsoft. If you can't find it through hardwaresource.com, Amazon.com, natman.com, rockler.com or macmaster.com, then you might reach out further and try Alibaba.com. Most tech companies, like Microsoft, are contracted to have ALL of their gadgets and hardware manufactured overseas and THOSE manufacturers are absolutely not buying any hardware through US, UK, EU or CA channels. It is all Chinese, Taiwanese, Korean or in cases where quality is more important than cost, Japanese.
And most of THOSE hardware suppliers will have some kind of presence on Alibaba, which is the third largest worldwide online retailer next to Walmart and Amazon, and has the largest sales volume in all of Asia. That's likely where you will find it or something like it if it is even available to anybody other than Microsoft.