I didn't replace it with an OEM piece, but when I did my seat cover swap I went to Jo-Ann fabrics and picked up a piece of foam. Then I cut out a square on the OEM piece and removed all the crumbled foam. Once that was gone I cut a piece of the foam I bought and glued it in to the OEM piece. With a razor and some patience I trimmed it down a bit to form to the original shape. This fixed it and the new seat covers replaced the worn out ones.