There are a few ranges of Maoris about: Empress Miniatures, Eureka and Wargames Atlantic come to mind. Eureka do some Hawaiians, too. Unfortunately I'm not too sure about how they all might line up style and size-wise, and a lot of the Maoris have guns, which you might not want.
Of course Pulp does make some rank-and-file troops designed to go with that set you indicated who would certainly be compatible, but they are clearly Melanesian, rather than Polynesian. Whether that would be a problem is up to you.