Once again, thanks to everyone who has come up with specific recommendations! If I seem slow to take them up, it is partly because I am away from home a lot.
I've also had to service my Mercedes Sprinter, which carries a motorhome body. Normally a service is about A$1,000 and this time I was quoted $1,250. It has only travelled 80,000-kms, and needed its first change of disk pads. The original quote did not include $1,000 for parts and oils! They spotted a slight oil leak from the steering, and told me I needed a new steering rack. By now the quote was north of $A11,000. I cut the non-essentials but still got hit for A$3,500.
This has postponed my record buying for a couple of months!