I got hold of one that will fit. It is a front wheel off an older model Rover Rancher which had that red powder coating. Most of that is peeling off in strips like plastic or vinyl. The aluminium casting underneath nearly always went powdery after a few decades, thus lifting off the powder coating. Compare that to older models that were painted and the paint and primer are still on them and no signs of corrosion underneath.
This is a slightly different hub, different design and held together with only 3 bolts instead of 6, but at least still the same profile and fits the 2.5-6 tyres and correct width/length for the axle shaft. Problem is I am now a bit mismatched, so would have preferred to at least have two the same, but "them's the breaks" I suppose. I am sure to pick up another one in future if I look around. There have got to be a lot of old Colts and Ranchers out there in backyards and paddocks just rusting away.
I am also fairly sure that these modern wheels available from Richmond will fit and are the right diameter (280mm), and have the same 6 bolt pattern as the old Rover ones, although requires an adapter sleeve for the bearing (1" to 5/8" reducer bush). But as they have rubber cushion tyres (not inflatable) and are slightly narrower, I am not sure how well they would work with Rover's "dog drive" system. In theory they should work, but that all depends on how "cushiony" the rubber is. At least they might be okay for the pull behind jockey seat. Only the Richmond ones (CR1110N-1) have a narrow enough profile of only 53mm hub length to fit the Rover, but oddly the similar-looking ones from EHI (WHD280/9315570910040) and Fallshaw (R280/70R-SRQ20) are both too wide (60mm). Also, whether or not it might be possible to undo the bolts on the Richmond wheel, remove the solid rubber tyre, and replace it with a tube and inflatable tyre might be worth investigating, but I am sure they will not have made them that easy to modify.
