Thanks for the suggestion.
I already tried Tony @ lathes.co.uk.
There is a Levin single step chuck collet mounted in the headstock but it is definitely not a Levin headstock. Under the large knurled rings are bearings, quite big ones, the knurled bit being just the cover.
The drawbar is 135.2mm long & solid steel, not hollow like most watchmaker drawbars. The drawbar knob screws on by a fine thread and then appears to be locked in place by an expansion screw?