Given you said it’s a desert trip and tow 2.6T at times then there is only ONE choice in LT 19. If you don’t buy them as someone said they are all pretty close. Just have two spares.
These cars are very back heavy and then towing with 1100 kg load rated tyres ( all non LT tyres) at recommended pressure they will be working at 100% load capacity ALL the time.
If you are heading off bitumen to me there is just no choice but LT rated.
2.5k for upgraded rims is an ask but tuff ant at 1250 roughly and some ko2 265/65 or 265/60 both in LT ( took Andrew st Pierre white 8 years to puncture one apparently) or the new Toyo rugged terrain and you’ll be pretty confident anywhere. All the above are 18” rims. A little whiny on bitumen but just put your current rims and tyres on when you get back if you don’t like the sound. Just my two bobs worth. Enjoy.your trip. Cheers

