Junkyard Barbie

A woman whose individual body parts are nice, but they don't match, so her body is like a Barbie doll assembled by taking various parts out of a trash heap.

You are with a friend and see a woman with a cute face, but her head is a bit big for her body. Or she has a nice bosom and an upper body that is right for a 140 pound woman, mixed with thin legs that look like they belong on a woman weighing 105 pounds. You say to your buddy, "check out the Junkyard Barbie over there".