Old sliding door roller replacement

I have come across this type roller in the past. The model is unfortunately not made anymore, but what I have done was to just swap out the wheel and reuse the housing. Take a look at the 81-223 1-1/8" wheel along with the 81-310 axle set, or even the 81-266 1-1/4" wheel and axle kit. This will be the easiest solution. 

If you can't reuse your existing housing, though, then your options become a little less promising. Take a look at the 81-023 and maybe the 81-279. These would take a little time and knowledge on patio doors to successfully adapt them to your patio door. If you aren't handy then I wouldn't try it, but a local pro may be able to get them in there for you.