Yep, definitely handy to match your vehicle and trailer tyres, but make sure you're camper can easily accept the larger tyres otherwise you're up for some expensive mods.
I think the Brumby handles those sizes without mods. I'm not sure the Daintree LE does. Don't know about the Spacevan sizes.
I looked a putting 265/70/17 on my Daintree LE but it would require a body lift and spacers and/or a longer axle