Thank You For The question XXXXXXXXXX,
I just looked up the carburetor and these parts are not available to be replace...the only alternative is to replace the carburetor...If you were to call around to some of the boating salvage yards, or dealers in your area. Finding one should not be too difficult...
Bear in mind that the screws holding the butterfly plate in the carburetor are "Staked" in the shaft and will likely break off if attempted to remove. Be very careful when removing them. We have removed the plates in the past to repair a sticking throttle shaft....
The diagram below is a 439450 carburetor....
Marine Mechanic
21 Years Experience as Mechanic, 18 Yrs Boat Yard Owner/Mechanic, Factory Certified