Is yours made out of Marinium? Mine is and it might be pretty hard to find that since I doubt it's made, anymore. Perko (maybe others?) still has a Marinium line, but it's the newer style fills. Definitely check around for an exact fit (maybe salvage yards?), but if not it would be easy enough to make an adapter plate out of Starboard to cover the existing screw holes and then put the newer/smaller footprint size one through that.