it is a newer laptop so it will be harder to find this.
It don't see it here on the ifixit site in the parts section.
ebay i guess, that is my answer for a lot of these sorts of things, just because that is where i get parts, rather then keeping track of a great deal of different parts web sites.
You might have to wait a bit for one to show up, i do see one on there now, ebay item # 160475666168.......it's from hong kong thou, which isn't usually a big deal.
You might want to message them first to ask them some questions if you have them, (is it OEM etc etc) they have sold a couple of them so it's up to you really.
You might be able to find more of them, I only did a quick look under the macs model number you have listed.