Vintage cast iron door stops are available on eBay and Etsy. To find these pieces in a brick-and-mortar store, the best places to look are local antique shops or flea markets.
EBay and Etsy both sell many types of cast iron door stops. The price and type of door stop varies depending on the individual seller. One popular type of cast iron door stop is cast in the shape of a Boston terrier. Other popular shapes include flowers or clothing irons. As of 2015, prices on eBay and Etsy range from about $50 to over $200.
Some stores also offer new door stops that look like vintage items. SignatureHardware.com sells a replica cast iron door stop for around $40.