Very timely thread.. thank you. I have the same issue, but not with fish.
I'm going to need to transport uncooked meat & some liquid to Kauai. My original thoughts were to freeze it all and then pack it in dry ice. With a $35 charge for dry ice, well, I may just take that 5 day cooler suggestion and just pack everything frozen with some peas thrown in for good measure.
We will be arriving in HNL on the non-stop, which arrives after dark, and connecting a few hours later to LIH, so I don't think heat will be much of an issue.
I was also thinking of 2nd day air-ing it, again, frozen, but since alot of it is liquid, it would probably be expensive.
Any thoughts on my plans?