Controlling the Iris remotely

One of the reasons I purchased the (3) Panasonic cameras was to be able to control the Iris from my monitor station when directing the three cameras. But, now that I have the cameras, I can't find a control box or the iris control pots to build a box. The only thing out there to purchase are individual VariZoom controllers (and the like) that mount on the tripod handles.

At church that I volunteer, they have just what I am looking for, but the box was custom built by a past member of the church.

Where can I go to find out what to buy or build? I also want to override the zoom function, so that is next.

Thanks,