DEF/DPG became mandatory only around 2009, earlier cars would not have that equipment, and a well-maintained eight year old Landcruiser definitely is up to a lot of abuse.
However, I think forester made a lot of top remarks; copy it and put it on your beware list.
We experienced the same in BC. Never believe that your 4x4 will get you out of everything that is thrown at you. Get some good support stuff. We once got stuck several hours on an otherwise good mountain gravel road. The rain had washed out a small grove straight across the road, a bit narrower on the high side and wider on the low side, but sharp edges and deep. We had a lot of miles to go still, so walking was out. The guy driving thought that it would be doable going as high as possible, but the lower rear wheel got stuck and pulled the other rear wheel into the rut as well. He tried too hard to get out at first, and we got stuck with the rear of the car resting on the ground, the rear wheels more or less turning without traction on the bed of the rut. No bumper jack, impossible to get the normal jack underneath a rear bumper or anywhere. Not enough equipment with us to do much, no handy tree stems or whatever laying around to help. Took us several hours to get the !@#@! truck out of that stupid rut.
Another good point: repairing a broken truck. A very good point. No matter how good maintained, every car can have a failure. Which means you need to be able to quickly and easily repair it locally. I hate to say it, but that goes heavily against Land Cruiser, Land Rover or Unimog. And for that matter, against ALL new SUV's with all their electronics. Never a car that depends mostly on electronic door locks, immobilizers etc. Most new cars here have only one door with a normal lock, the rest is electronic. Very nice, but if your main battery goes out or your remote key battery, you cannot lock your doors anymore. If a battery is flat, you can be up the creek in a major way.
For that, diesels are always better than gas. Less engine maintenance, less dependance on electronic: if your battery gets blown, as long as you can get/keep the engine running, you can continue. With a gasser, once your battery is dead, your car stops also.
I slept in the back of the Chevy with the plastic cover with -25 Celcius (-4 Fahrenheit). No problem. The cabin provided the shelter, the mattress and the down clothing the heat. I also slept in the back of a Toyota J40 short base, but that is too crampy. A long-base would offer the same comfort. Camper in the back: bad idea unless you drop it somewhere off, leave it there as base, and do the real wilderness without the camper on the back. Those things make the trucks have and much more unstable.
For that matter, you might take the older Toyota Hilux or Tacoma (both real pick-up variations) into consideration as well.
Having said all that, my preference say different but to be honest, I probably would go for a 10 year old Ford, Chevy, or Toyota Hilux 4x4 workhorse with the smaller engines. You don't need the most powerful 8 cylinder engine. With a light to average load without trailer, the average 2.5 - 3 liter engines probably would do the off-road work as well if not better. The lower weight of the smaller engine gives the car a better balance. Give everything a good makeover. If really wanted make a flexible connection between cabin and back but do not make it into one long unit; I saw that in terrain the rear part quite regularly was a bit twisted from the front cabin.