Last week I met a roller I had never seen before. Two in fact.
They were in a sliding door that dated back to the 70s, so they were almost as old as me and were obsolete with a capital O.
Problem was, though I had similar sized new rollers that could have fitted in the bottom rail, these rollers had bolts screw into them from the top and side and were integral to the construction of the door.
The nylon wheel and steel bearings were shot – but the chassis was sound enough, so I carefully drilled out the old axle, replaced the old roller with a new one and reassembled the door.
Job done and considerably cheaper than a new ranchslider! A bit of recycling and reconditioning can go a long way.