I use travel insurance when I go to remote places around the world. The cost is affordable. I usually use TravMed. I've been lucky, and never had to rely on this option so far.

However, I don't recall any policy from them about providing cash in the event of an emergency. It's actually a really good question. Suppose you are safe - you manage to get away from a bad location - but you need cash now. I guess you can always go back to the time-tested routine of washing dishes at a local restaurant. Hahaha !
Most travel policies cover emergencies ... usually the costs of hospitalization and evacuation. I don't think they offer money.

The suggestion above to make an emergency phone call to AmEx is probably an excellent idea.

Pete2