After some further mental gymnastics, the plan I've come up with which seems to most greatly reduce the disquiet is to buy a backup cellphone, small enough to turn off, stick in a pocket and forget about until I drop my smartphone in a stream. Something along the lines of taking one of the watchphones from http://www.dx.com/s/850%2b1900?category=529&PriceSort=up and snipping off the wristband, or one of the smaller entries in http://www.dx.com/s/850%2b1900?PriceSort=up&category=531 ; along with the $25/year plan from http://www.speakout7eleven.ca/ . Something on the order of $65 to $85 seems a moderate price for peace of mind.
I am, however, going to take at least a day before placing any such order, to find out if such a plan still seems like it /will/ offer increased peace of mind. Not to mention, whether I can come up with (or get suggestions for) any plans which reveal that my actual disquiet arises from some other cause.
Have you gone camping like this before? If you have, were you by yourself when you did? I'm just trying to eliminate the source of your unease being something simple like stepping out of your comfort zone.
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