Me again.
I've spent ages Googling, and looking through eBay and Amazon, for replacement suitcase wheels, without luck. They are black, 115m outside diameter. The wheels are 23mm wide, but measured at the bearing that's 30mm. The axle is 6mm, and 40mm long.
Everything I can find is smaller, even though these don't seem remarkably large. Any suggestions, short of paying £25+ for a scooter wheel?