5500/5700 series roller

I'm afraid that's not enough information to make a recommendation. The only way we'll be able to pick out a matching roller from our inventory is to see the original. I know that's more work than you wanted to put into this project, especially without having the replacement part on hand, but there is no other way. This isn't a quick project. You need to be prepared for a significant investment of time and effort.

Once the roller is out, I would like to see a clear picture of the back end, top, and sides. Written dimensions will also be necessary. Once I have that data, I will check our inventory to see if we have a good match.

We have no definitive record on that door, no. I'm not even sure who the manufacturer is. It might be Silver Line but that is mostly an educated guess. Either way, Silver Line has used many, many different rollers on their doors and at this stage I have no way of narrowing it down. 

Seeing the old roller is the only way to find a match. Like I mentioned before, this is not going to be a quick project. You will likely have to remove the old rollers, take photos and measurements, then put them back on so that you can set the door back up. That does mean you have to take it down a second time once the new rollers come in. This is a lot of work and will require at least two pairs of hands.