The tyres you are running are considered oversize so when you replace and dependant on rim width, go for the far better size of 265/40-20. This is the go to size for T32. Pressure wise. Drop them to around 36, up to a minimum of 40 when loaded.
Suspension wise we have plenty of options for your camper- presently it’s running van suspension designed to carry over a ton, hence the skittish ride. A decent suspension setup right and alignment correctly with the right tyres will completely transform the look and drive of your vehicle. We offer fit on site and mail order. Always happy to have a chat on the phone to help.