I have an old set of rollers - about 10 yes old. They are foldable.
The rubber band never really stayed on terribly well , so I attached a couple of old CDs to keep the rubber band from falling off at high speeds.
They have been sitting in my garage for a few years now. Possibly they could still be used to, or at least the rollers themselves might be of some interest as spares.
If you're interested, send me a PM.
Collect from near Gerrards Cross, South Bucks. Could take them to Gerrards Cross station if that would help.