I had this problem too, tried a print roller refurb place, first batch OK then the second batch were very mixed sizes. Eventually I refurbed them myself by stripping the rubber off ( heat it with a hot air gun and it re vulcanises ) and found some silcon tubing with the right ID and OD, slipped this on the clean metal roller with a bit of silicone rubber to hold it in place, this worked for the last 12 months of life we had in the units before replacement.
