Arms and Hand Lifecasting Recommendation?

Dear Lifecasters,
I am searching for an appropriate material to use for molding arms (from the shoulder to the fingertips). I would like to use plaster for the casting material. I've tried molding my arm and hands with flex-wax, however find it difficult to mold an entire arm. I am looking for an inexpensive material, and therefore am hesitant to use alginate. Detail is important in the hands, but not crucial for the arms. Would plasticene work as a mold material, keeping its form well enough to make a plaster cast? Any advice would be greatly appreciated.
Thank you, Christine