There has to be someone near where you live that fixes small engines. All mechanics keep boxes of old carbs and every other type of part for that matter. Probably get it fixed for less than 10.00 that way. Might evan be able to get a good used replacment carb. If you are not using a velosity stack you can make a choke out of a thin flat piece of steel or plastic. Drill it to rotate on 1 of the carb screws to cover the intake. Hook it up with a pushrod to operate inside the cowl. make it spring loaded to stay open in flight.