Crit.. I have a set of basically brand new 2017 18" but my guess is that nobody, like myself, is willing to sell just 1.
So I have some good news..I live in Sacramento. So If you are willing to give me $500, and drive up to get them, you have have all 4. Then (So you are spending $350 more than you want. But then if you can sell the other 3... well you will probably be just fine.