Sorry for going dark like that...the situation has changed and I can't sell the head/carb separately. It will go with the car (
http://www.minimania.com/cars4sale/14155/1970_Austin_Cooper_1275_S_Sedan_1275cc).
But to your point, 12G940 sounds familiar although I don't remember for sure. The stuff is mounted on the car and I haven't had a chance to check.