I may be wrong Deejay, but I have the impression that the Rover version contained some additional cheapening features, such as a single row self aligning bearing on the clutch shaft, instead of the two row one used on both SB versions of the mower. I have a feeling there may have been other negative developments. That would, simplistically, give us three versions of the mower over time, each of which was inferior to the one that came before. Perhaps we could even say that the SB45 itself may have been inferior to its predecessor, the SB33?
The problem of high prices and limited availability for the older SB45s in WA has been highlighted at least once before. I tend to see this as more of a logistical problem than a barrier though. There should be some way to get a mower transported to WA.