Sounds like a ripper of a sail to me.

On two separate occasions I've shipped a sailboard from Perth to Sydney. I used one of the major courier companies, think it may have been TNT. The cost was around $80 to $100, and it took about 5 days. The sender covered the boards in a generous amount of bubble wrap, and then placed in a carboard box, with some extra cardboard placed over the nose, tail and rails.

Regards,
Harrow.

Go to Mackay, spend a week or two test riding the board, taste local produce and sample beer and then bring it back as luggage - you'd have enough brownie points!