I agree that it looks like a pinata bat, but most pinata bats are hand-colored.
How heavy is it? If it is a pinata bat I would expect it to be relatively light weight. If it is heavy, I would think it could be some sort of ceremonial Indian club.
Here is what came up on ebay when I searched Hawaiian bat....
"The Flyin' Hawaiian"
www.ebay.com/itm/221261645864