Is it possible to get new carbie for a Kawasiki TG18 brush cutter ? ?

My Kawasiki TG18 brushcutter must be 15+ years old. I can no longer get it started. For the last few years every time I go to use it I have to adjust the Hi / Lo mixture screws and beg it to start. Can I buy a service kit for the carbie or better still a replacement carbie ?
The cost of having a professional work on it exceeds its value, thanks, Trev [Canberra Australia]