There were some metal ones recently on Ebay, maybe a set or two. I don't recall if they were 6 or 8" though. They were all black from what I recall. Perhaps do a search on "completed listings" and you'll find the original listing. That way you might be able to contact the seller to see if they have any other ones. I need one for my Sequoia as well, but mine are the plastic hub with rubber tread.