We don't post a flat number for roller replacement here because it depends on how many rollers need swapping, whether it's nylon or steel, and whether the track needs straightening at the same time - that last one is common enough on Star's newer doors if a roller seized and dragged before anyone noticed. What we can tell you is that a full-door roller set generally runs well under a spring job, and partial sets (just the bottom two, which take the most wear from opening and closing) cost less than the whole run.
We quote the job on site, after a look at the track and the existing hardware, not over the phone from a guess. Given the median household income here runs higher than the wider service area, we still price the part and labor the same as anywhere else we work from Meridian - the job doesn't change because the street does.