Hi and Welcome to the world of Kawasaki sleds
What year is your Drifter? Different years have slightly different engines.
Parts are available, You just need to find them, There are lots of people on here that will help you.
John Deere Sportfire's have the same basic engine. But they have different exhaust.
The carb should be a Mikuni vm32 with a power jet (same basic carb as a 340 just jetted different)
Good luck, ask lots of questions and pics are good!!
Lloyd