It appears to be a 1" OD by 1/4+" wide with a 1/4" hole ID that does not go all the way through, thus keeping the wheel from moving too far to the outside and providing a slide to keep the drawer aligned. I think it is made of nylon or hard plastic.
Tom from SWISCO responded:
October 19, 2017
The closest match we have to your dimensions is our 32-039. Look over our pictures and information and see if you could use this to repair your drawer.