Here is the inspiration piece that inspired Joyce Growing Thunder's figure, front and back. It is a Girl's Cape, Assiniboin, from 1890-1905.
You can search the Metropolitan online data base for photos and information about museum objects and collections, including Joyce Growing Thunder:
Lastly, I love this figure in the Museum. I’m afraid I do not know what it is, but I call it “Curmudgeon Baby,” because that is what it looks like to me! Cute Curmudgeon Baby.