It would be alot easier & cheaper to change the ignition switch. You have to take the switch out anyway to go to the locksmith, which is going to charge you about $75-$125 just to cut a key. Go to your local boat store with the old ignition & buy a new one.
Hello I work for the Napa distrubition center in detriot and i also lost my key so i just replaced the ingnition switch so basicaly what i'm getting at is if you have a Napa auto parts near you should be able to get the new ingnition for about 15 bucks i paid right around 20 for mine which is a push to choke. Good luck.
