jadejohnsonindustries
Ah! Through a lot of digging, I found the real answer. Based on the height of her oar on the movie's cover-art, she's seventy-three-percent shorter than it.
Some guy at "TheyDidTheMath™" Googled the average length of an oar, then subtracted fifty-centimeters, due to the production-challenges of Moana's would-be time-period; and with a percentage-calculator, he discovered that she is almost-exactly five-feet-and-nine-inches-, or about a-hundred-and-seventy-five-centimeters-, tall. That does seem just about right, doesn't it?
But hey! Maybe you can update your model and make her as accurate as possible: I'd love to see that!