Looking For Pan And Tilt Unit For Megapixel Camera

That sort of thing used to be pretty common but, so far as I know, no one has built anything like that for a long time.

Something like this Undisclosed:

http://www.videotec.com/en/page_393.html

?

12 kilograms? That's over 26 pounds - one hefty camera. Did you mean 1.2kg?

Anyway, Pelco still makes pan/tilt positioners. Take a look at the Pelco Legacy Series Positioners. You will also need a power zoom lens if you want that capability. Here's a link to their Spec Sheet. You will also need to specify a Legacy Receiver and choose between fixed and variable speed, which pan/tilt you need (PT780-xxx) and any accessories. Control would likely be via RS422 using Pelco 'D' protocol.