Are Stinger missiles able to reach 30,000 ft cruising altitude. Were other weapons capable of doing that likely to have come from Libya? Did Ghadaffi get gear like that from Russia? What irony if true.
London reporting a shootdown.
All bets are off
Shoulder launched “stingers” (manpads) of US origin maybe. Russian definitely not.
Ghadaffi once had SAMs able to go that high - but were truck or fixed mounted installations, not man-portable; don’t know which designation, but were launched at an SR-71, but were too slow to catch up ...
Best weapon I could find which was in Libya and could have been smuggled to Sinai was the Russian Igla-S or SA-24 which can go to 19,600 feet. There are mountains in that area so they could have gained another 2-3000 feet, which, if the plane was not yet at cruising height, could have been taken it out.
If, maybe, perhaps ... too many variables to say for sure, except that reports say the plane wreck looked like it was hit by a missile.