I recently bought an Astra Meca semi-universal dividing head, which came with a 3-jaw T de G chuck on it.
There's a picture here:
Also.... I'd quite like a 4-jaw for the dividing head too, but I've no idea what the mounting is. It looks like 4 bolts onto a flange, but this is all a bit new to me; again, does anyone have the info to hand? The Astra Meca manual which came with the head is a bit recitent (= totally silent) on this question.