Well, I have one to sell but I am in Michigan and it isn't worth shipping.
I bought my work cart on ebay
and I also have a friend that bought her show cart on ebay. Also try www.tacktrader.com
and search "cart" they have a lot of ads for carts on that website. Craigslist would be a good place to look also and you would be able to search local listings. Good Luck!