Considering that the script for the movie was written before the release of Pocahontas it's also a pretty weak joke.
The correct one would be dances with wolves, which was released in 1990.
I really don't get the Na'Vi = American Indians angle though. Although there's obvious influences, like their facial structure, their dress is closer to those of traditional African tribes, as well as their situation (being exploited, relocated and killed by corrupt western mining corporations).
All things considered though, Oblivion or Fallout 3 would be far better games to base a mod like this on, if only due to the fact that unlike M&B they can produce decent forests. If you're set on M&B though, try making some items or some of the basic modding yourself and put some screenshots up, you won't get volunteers unless people know you're actually serious about making the mod and willing to put some hard work in.