I'm never going to leave cell phone coverage, haha! I have seen three options that do not include roadside assistance:
1. Tire repair in a can. I've seen ones that claim to be safe for TPMs. I'm not sure if they'll ruin the tire/void warranties, but they do claim to clean up with water.
2. Onboard repair kit: compressor and liquid latex sealant.
3. A mini spare wheel/tire and tools -- I haven't researched this much.