There are a few options, depending on what electronics you want to put in it. If you are looking for a topper that won’t need to use a hollow stalk, hit up animefan, but I’m not positive he is still making them. There is another guy here that makes them, but I can’t remember his name other than it starts with a U. If you want to go a more accurate route, you will need a hollow stalk and a topper that can fit a kit that uses wires and the Honeywell switch.