Where can i get cheap Good Smile Nendoroid Vocaloid Figures from?

Where can i get cheap Good Smile Nendoroid Vocaloid Figures from? I am looking to find and buy these two figures Good Smile Nendoroid Vocaloid Len Kagamine Figure and Good Smile Nendoroid Vocaloid Rin Kagamine Figure. But i can not find a place that has them for sale and is fairly cheap. Can anyone tell me where i can get them from please. As soon as possible. Thanks