Organism is a must.
I've had no experience shipping fish , so people can correct me if necessary but I think a 5 hour trip should be OK. People ship fish from one end of the country to the other and imported fish are in transit for who knows how long. See if you can get one of those small polystyrene boxes or a small chilly bin to reduce heat loss. Even wrapping the fish bag in a towel would help.
Tell the LFS that the fish are in for a journey and ask for a larger than normal bag, or bags :lol: to maximise the water / fish ratio.