You can get a custom, to your specs, from Accurate Molds in Salt Lake easier than you can find one. Last one I got, was a custom single cavity aluminum, to my door in less than 2 weeks, for under a 100 bucks. You just cruise their site, pick your style number, fill in the dimension blank boxes, specify your preferred alloy to be used, Tom calculates the final actual cut dimensions of the mold to produce the right size for your throat, submit your credit card, watch the mailbox. Done.