Spline drum break actuator arms

I have a Fox Sundowner and am missing one drum break actuator arm. The cam pin is splined instead of square like the Rupp cams are. I've seen lots of splined actuators for motorcycle rear drum brakes on ebay but I don't know if they're the same size. Has anyone used a motorcycle drum break actuator arm on a mini bike? Specifically a Fox bike? The cam pin is 1/2" diameter with 30 teeth. Drums are 4 1/2" diameter.