Where can I find a replacement throttle cable

Hi Ren, it doesn't appear that Mantis sells that throttle cable, and neither does Honda. They don't have it listed in the parts catalog for the 7566 Tiller. Generally speaking, when a throttle cable breaks on a small engine, I measure the cable and purchase a universal kit of the correct length to replace it. You can find these kits on Amazon, or at your local hardware store.