handheld aviation radio for backpacker?

I've got a friend of mine who is going backpacking in Alaska for a
couple of weeks. He has expressed an interest in borrowing my handheld
aviation radio to use in an emergency so that they can "flag down" an
overflying aircraft.

I don't mind lending the radio, but I don't think the radio affords
then very much protection. In order for it to "work," there would have
to be an aircraft overflying their area *and* it would have to be low
enough for the handheld signal to reach it *and* it would have to be
monitoring 121.5 or otherwise be on the same frequency. (I guess I
could find him an ARTCC frequency map for the area in which he'd be
hiking.) Maybe in Alaska monitoring guard is s.o.p., but where I'm from
(NorCal) it doesn't happen as much as it should.

Is there really any reasonable chance that this would be valuable to my
friend?

I have suggested they get a personal 406MHz ELT, but they are about
$600 for a regular unit, and $700 for one that also incorporates a GPS.
Are these things available for rent?

Also, can one rent an Iridium phone reasonably? That seems like it
would be more useful for this purpose.

Anyone have thoughts?

thanks,
-- dave j
-- jacobowitz73 --at-- yahoo --dot-- com

PS -- I know it's also illegal to operate an airband radio for a
nonaviation purpose, but I figure I should not be too worried about
that, if they really intend to use it in for an emergency only.