I have no idea the manufacturer. There is another housing that is still inside the bottom rail of the door..
The wheel is 1 1/4 diameter. There is a bottom screw that is accessible on the surface of the side rail. The up and down adjustment is accessible through a recessed hole right above the other screw
That other housing is an important part of identification. Without seeing the complete assembly together, I'm afraid I can only guess.
Looking at what you have in your photo, our 81-022 may be what you need. However, I highly recommend removing the housing that's still in the door to confirm that it's the same style. If it's not, we need to see it.
