I think you need a Z20 or Z29. Can't remember which. You might check here for SF parts:
LPS
They have a much more complete list of parts and accessories than SF's own website or catalog. For whatever reason, SF just does not want to tell us about lots of things they have and sell. I don't understand this, but they are very stubborn in some ways.
This came up recently when I asked in the LED forum about modding a KL1 head to a color LED. Someone said I could buy one and pointed me to a dealer that has them. SF makes them in Red, Green and Blue, but you would not know it from them.
Mark