Do you want a functional equivalent, or do you want a part you can put in the existing circuit without any adaptation or modification? In either case it would be handy if you could deduce the schematic from the board so we can properly advise you.
how abt I replacing it with 4N60 or 4N80 which are available in the electronic store at my place....both of them are very nearly rated to it.....One a lil high and the other a little low