Spare tyre no.

2 absolute minimum.

G'day, a couple of tubes the right size are good, takes up little room, can be a lifesaver

As you have interchangeable wheels and tyres between your vehicle and van, you already have two spares and shouldn't need any more.

If the existing wheels are tubeless, a plug style repair kit is an invaluable investment and will allow you to repair most punctures without taking the tyre off the rim.

A tube of the right size is a further form of "protection".

I carry a Tyreplyers kit, a plug repair kit and a tube that will fit inside the tubeless tyre if necessary.
The only "puncture" I have experienced was a completely destroyed tyre with large holes in the sidewall that no plug kit or tube would fix.
Anyway, if you have the basics as identified above, you won't need anything:-)
It's all a matter of Murphy's Law.

One other piece of advice I will offer and it has nothing to do with punctures.
Ensure you have very good stoneguard protection when towing. A tiny stone flicked up and bouncing off the A-frame of the poptop can destroy your rear windscreen and put a dampener on your enjoyable trip. You may also experience major stone chips to the front of your van unless you prepare.

A stoneguard mounted on the A-frame of the van with flaps underneath will help protect the van and limit the chance of damage to the rear window.
To best protect the rear window, a rear screen saver, or even taping up the rear window with cardboard is a very wise form of protection.

There is a section on the northern part of the Birdsville track that begs you to try your luck without this type of preparation. (I know cause it's happened to me)

I now have a stoneguard on the A-frame of my camper and also mount an exaggerated mudflap on the vehicle behind the wheels, to restrict stones, etc., from being spat out the back.


Bill.