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We do not have a direct replacement for the roller you have but there are a few options that may possibly work for your repairs. Start with reviewing and comparing the 81-138 Patio Glass Door Tandem Roller and the 81-157 Tandem Patio Rollers. Be sure to compare all of the dimensions to determine which of these would be the best fit.
If you do not believe either of these rollers would work for your repairs, the other option would be to reuse the existing housing (if in good condition), replacing only the wheels and axles. To complete this repair, you'll need the 81-266 1-1/4" dia Roller And Axle Kit. Take a look at the video tutorial below for reference.