There are a variety of rollers, just search for 'slide roller' online, and match one up to the height you need for where yours is mounted.
Sometimes they can be tough to get to - you may have to run the slide in half way and tilt it out at the top to gain access under it at the floor.
I would like to replace my bedroom slide glides with rollers and put a new floor in there - I can get access to the mounting area under the bed.
In my living area slide I cut the carpet about an inch from the floor of the slide when it was all the way out. The floor in the slide part, which is under the dinnette, is also still carpet.
Notice even some of the newest units still have carpet under and over the slides with tile or other hard flooring on the traffic areas.
Making it all work and look right can be a bit of a trick - get creative.