Quote:
...Since many survival situations start once you become seriously injured, I consider an option that I might be seriously injured and have to rely on external urgent help while trying to stay alive. That’s why it is communication, medical kit and shelter. ...

Many situations also start with someone becoming lost. Make sure your kit includes navigation. Staying found is big and if it turns into an E&E you really want to where you're going.

Edit:
After some thought, either of the Garmin Foretrex GPS receivers or the newer fenix™ GPS, all wrist-worn would work. I kinda like the fenix™ because it looks more like a standard digital watch. Unfortunately, the downside is that Foretrex units require batteries and the fenix™ requires a source to recharge.