Looking for a patio door roller

Thanks for posting. We can help you replace these rollers, but this is actually not the entire roller. This is just the inside portion; there should also be an outer housing. It is likely still installed in the door. In order to identify the roller you need, we will need to see the entire assembly removed from the door and put back together. The width and height of the entire assembly, as well as the diameter of the wheel, would also be most helpful. Many thanks.