Gas Cap - Craftsman 4.5HP Lawnmower

The other day I was mowing the lawn and a horrendous sound came from with the bowels of the beast. Looked down and there was the gas cap cut and bashed apart. There was little time to go to the store and I couldn't leave the yard half way done with fathers day coming up. No father wants to cut grass on fathers day, I wanted to spend it with my kids. So needless to say I finished mowing the lawn with no gas cap. Dirt and grass clippings flying dangerosuly close to the opening of tank. Then