3/4 in. offset, backset closet door roller

I am looking for a 3/4 in. offset version of the rear bypass hanger E-Z Roll model 23-178 (1 1/2 in. offset, backset), in which the base of wheel appears to be much closer to the top of the door than in the case of the Cox 3/4 in. offset, backset roller (Home Depot). Surprisingly, none of the suppliers/manufacturers list the distance the roller wheel sits above the horizontal plate of the bracket. This is a critical measurement when looking for a replacement part.