@Tulipe: Yeah, the pants are definitely skin-tight, so spandex is probably needed. I'd just order a pair of leggings (you can even get the exact same shade of green for the gloves if you use welovecolors!~)
As for the top, I'd probably lean toward making it fully boned for the form fitting shape. Maybe a matte polyester satin lined with cotton? Or moleskin for a more earthy feel. (I used moleskin for my Briar Rose skirt and bodice, as an example: http://www.cosplay.com/photo/3141449/
and it drapes beautifully!~)
@Link: I'd lean toward polyester blends lined with cotton with interfacing for the "shoulder pads"