Cracked Rear Cover on Note 5. Where to buy OEM replacement?

I have been reading in various forums about replacing the rear glass, however there seems to be a lot of fake, plastic cases out there. I called Samsung, who don't carry the part directly. They have a distributor that sells their parts, however they don't even list the rear cover at all.

Others have said they are glass, but reviews state they are plastic. I just want to replace it with the correct part. Does anyone know where to purchase the actual Samsung rear cover for the Note 5? Thanks for the assist.