I don't know what it is you have now, so I'm not sure what to recommend. If your patio door track has dents and divots, you could install a track cover like our
80-102 on top of it. Refer to the video below for more information on how these work.
You could also try cleaning and lubricating the rollers and track to see if that helps. If not, though, then you may need to replace the rollers entirely. There is only one way to find replacement hardware, however, and it will require you to remove the old parts entirely so that you can carefully go over their style and dimensions, then compare those physical aspects to the various replacement options available. I'm afraid there is no other way. If you were to show us a picture of the hardware you need out of the door, we could help expedite your search.