Best way to access money in the Cook islands

I'm Aussie and heading off OS again - this time to the Cook Islands (and NZ). Taking some cash but have a few big ticket things to pay for. Wanted to use ATM's to access money but the banks, and now even my Mastercard, are wanting to charge me $5 fee + 3% foreign currency fee for withdrawiang form an ATM! What a rort! I'm sure the credit card company never used to charge but there you have it.

So....any ideas on the best way to avoid paying through the nose to use money abroad? Any experience of traveller's cheques in the Cooks? How about those Travelex Money cards?

Thanks for any ideas.

I used travelers checks in the Cooks in 2006. I exchanged some at the currency exchange window at the airport upon arrival and some at a business that also did currency exchange downtown. It was very easy, I don't recall paying a surchage.