The roller assembly is 3/8 inch wide while 2 inch long. The wheel is 1 1/4 inch.
The roller assembly I removed appears to be the same as 84-016, but after looking at a few more the all seem to have the same measurements. Removed from a Milgard screen door.
Tom from SWISCO responded:
August 10, 2016
Thanks for posting. I agree, the 84-016 looks close. If all the dimensions are the same I think it would be a great replacement option.