I run the OEM recommened 195 thermostat and it doesn't get near that hot, even in the summer in Texas.
I could be wrong but if the thermostat fails, it fails open meaning coolant will always be running through the system and it will take it longer to heat up.
I encourage you to get this addressed ASAP, meaning before you do any towing. If it's overheating, something is wrong and a cooler thermostat isn't going to fix it. If you don't address it you're risking serious damage.
Set aside a day and do it right. Drain the coolant from the block, flush the system, replace the thermostat and antifreeze (70% antifreeze-30% distilled water), and change the radiator cap. And by flush, i don't mean just run the garden hose through it for a little while. There are better ways but the Prestone Flush should do a good job. If you can work it into the budget, change the hoses (probablly $60) and water pump ($60) while you're at it.
Also, make sure you remove any debris in the radiator fins, that can cause it to run hot.
Seriously, make this a piroirty. I didn't 15 years ago and it was an expensive mistake.