Around 900A.D to the time the dutch discovered Easter island (rapa Nui in 1722)
Archeaologist believe that the statues where built around 1200AD of course that is not for sure because they were not discovered until the 1950's.
If you mean by 'trunk' the body from the waist to the chin, it's called the torso.
it is an island found in the Easter islands that is why you don't hear of it because it is almost always associated with the Easter islands.
Rapanui Clothing. you can find it at www.rapanuiclothing.com i think