I've been in a lot of those areas too and I do not worry about it. I carry a lot of spare parts including a unmounted spare tire and the jack and tools necessary to change/mount it. If I cannot fix it myself then I'll get in the car that I pull and go find the necessary help.
If you are stranded... no second vehicle then I'd make a sign: "Broke down, No cell service, need a ride to xxx town." Stand beside the rig nicely dressed and stare at every driver without your sun glasses on. Someone will stop and pick you up. Let them see you write their tag number down and hand to the DW. Take your sign so you can hitch a ride back if necessary.