I think the ball on the I3 is 17mm diameter, I have used a camera mount and a piece of polycarbonate for my I3 (and knotted string) If you find one please let me know
thankyou, very promt....do you have a 1" ball-i3 ball adaptor? as that would be all i would need to use it in my current set-up on the fireblade kind of like this but differant size balls on each end