Something wrong with the levers, or the cables that link them to the engine? If you really want to replace the levers, it would be nice to know the manufacture of the productd you have. Probably Morse, if they are not on a Pedestal, like Edson, for example. Morse was purchased by Teleflex. All this stuff can be purchased through any knowledgeable marine store. They might not have it in stock, but can order it for you.