Wico twin cylinder magneto wanted

I am trying to find a magneto for a Petter PA2 engine. The magneto needs to run anticlockwise. The engine manual states that the magneto number is either A1114Z or A1116Z depending on rotation, (but does not say which is which). Don't know if the correct part number is required to go with the engine or that any Wico series A twin magneto of the correct rotation will work. If anyone has information regarding such a rare beast I would be very grateful.