Barnes turned me on to these:
They hold 50 lbs of frozen or cold fish.
You can stuff 2 into one and fly them down with you. We did that for our Cedros trip and it worked slick.
When I have fished PV i ran to the store and bought basic igloo 40 quart coolers and put exactly 50# in each.
Last time I brought home 3 and paid the baggage fee. They will make you have them plastic wrapped at the airport during check in.
I'd leave your coffee grinder at home. Go, listen, learn.
My write up from last Thanksgiving down there: