Mike
I helped start a dive operation in Panama, Panama Divers. A good friend Clay Jorgenson is the owner. They have several boats and may be able to help with logistics. Oxygen and helium is available in Panama City, and rather cheap as I recall. Panama Divers runs trips out to Coiba on the pacific side, not sure where on that side you are headed, but Clay can help you out for sure, tell him Cliff sent you. I am long overdue for a trip back to PTY, when is your expedition planned?
It's funny an outright lie brought me to Panama in the first place. This guy claimed he had found a cave and laid 1000ft of line and need help surveying it. It turned out to be a sea cave formed by surge and went about 70ft. However the other people I meet there on the hairy edge were very cool. The guy who lured me to pamama with a lie, has all but killed himself with cocain addiction which is dirt cheap. My interest lies on the atlantic side east of Colon, looking for more shiney yellow stuff...
Good luck with your expedition.
Cliff
cavecliff@yahoo.com