you can already order those from Japan. I saw some that sold for over 6Gs. made entirely from surgical grade silicon, and come with 4 different color wigs, and taped voices that apparently synchronize with whatever you are doing to them at the moment. apparently they are big sellers among officers in their merchant marine fleet. come complete with vibrating oral features etc...
Forget silicon. I want real flesh, saliva, and juices. She doesn't have to have a brain, but the rest is mandatory.
A primitive brain would be nice, as I want her to have orgasms and be able to follow instructions.