The wheel appears to be 15/16. The bracket it 2 and 3/16 long and 9/16 deep
Tom from SWISCO responded:
March 14, 2019
Unfortunately, we do not have a replacement for this roller. I don't think this is made anymore. Your only option would be to use our 23-250, 23-251, or 23-252 replacement pocket door track kit. I'm sorry that we cannot be of more help.