DeLorme Inreach Explorer GPS doohickey. Has satellite SMS texting capability with an SOS feature. Comes with optional $200k rescue insurance for $12 per year. Just a though, but I could have mis-read your intent.
There is obviously an initial cost, plus a basic monthly subscription. This is well worth it in my mind - but in the off season I'm snowmobiling in the back country so I use the device religiously all-year-round.
Sent from my SM-G900P using Mountain Buzz mobile app
"Good judgment comes from experience, and a lot of that comes from bad judgment." ~ Will Rogers