Hubcaphaven.com has reproduced OEM wheels a little less than $300 a wheel for the 18" Ebony
https://www.hubcaphaven.com/mm5/merchant.mvc?Session_ID=8e0cdcb7c216d7cfa23b7d23dee8a810&Screen=CTGY
If I ever become insanely rich this is one of the things I'll buy...someday. My luck though they'll quit making them just at the same time I could get one.
It's a feature I've always loved. I can't wait to have it again when my Fusion is in. I love it in my work Expedition too just in case the keys get locked in it or I don't have the keys and need something out of it.