I have what I believe to be the Alexander version of the same head.
If you go back through Stephan Gotteswinter's (I probably butchered that last name) youtube lists, he shows one while using his Deckel Panto Engraver.
Also on his site
Deckel G1L engraver – Stefan Gotteswinter
Oooh. Just noticed. Yours IS an Alexander version (the GHA marking on the edge of the tilting table!) George H. Alexander, IIRC, who was either the English importer and seller of things Deckel, or was licensed to reproduce them locally in the UK. Or he just plain was ripping off the designs, but like as not THAT would have been newsworthy enough to be on record somewhere. I have not had anyone tell me anything but supposition so far...
Just ran down and grabbed mine. Mine has a Pratt Burnerd marked tommy bar chuck, no GHA markings, and has been mildly modified by having the scallop beneath the chuck when it is upright, hogged out a little deeper to provide clearance, likely to allow the jaws to extend a bit more when working on larger diameter items.
I worked on the assumption mine was a GHA, as it has the British made chuck on it. Dunno if Deckel used PB chucks on theirs.