Many times, you can go to the hardware store and replace the gasket with an o-ring.. Doesn't always work though..
When you get it running, pour about 5 times the recommended concentration of carb cleaner in with the gasoline.. also make sure to add STA-BIL.. let run for 15 minutes and store for a couple weeks..
Then start it back up, let run for 15 more minutes and then shut off fuel supply and let it run the carb bowl out of fuel for storage..
You should be good to go for winter when it comes.