X-2000 X-2000R tension arm roller black cap

I have had these on my desk for weeks, I have come to the conclusion that these are the ultra rare tension arm roller cap for the X-2000 series , that was the last reel to reel they made for the hi-fi market.  I have never seen one , but I know its super finnicky on its transport side.

Owners who have them preferred the earlier X-1000 types 

I am still not 100% sure on this so I have included the dimensions , these are impossible to find