Well since the airframe is pretty much in one piece, the 406 ELT would have gone off and rescue will be within a day or two at most.
When I traveled a lot, I took a portable printer with me, maybe one of the pax did the same? Check the cargo, maybe someone was shipping a small diesel generator (they will run on jet A) if you want a more "McGyver" kind of thing, and a tight power budget to boot, have a box of thermocouples in the cargo. Strung together with any kind of a heat source and you can get some power.
Check out how the RTG's work in spacecraft like Voyager or even some Russian lighthouses worked for the idea.