Rollers for patio door, no known manufacturer

I could be wrong, but your roller housing does not appear to be 1-1/2" tall. It does look like it has mounting holes at the top of the housing, though. With that in mind, take a look at the 81-138 roller with the mounting hole on the top of the housing and the 81-176 with the mounting tab. These are two examples to get started. We have detailed photos and measurements on their store pages that you can look at to confirm. Also look at the related videos, they may be a big help.