I've been rebuilding a British made HC Chucker over the past six months, and your HC looks like an earlier version of the one I bought on Ebay in March 2012. I believe the early models did not have the self-indexing feature to the turret. The Fetham Middlesex address suggests an early machine, as later versions were manufactured in Exeter. However, the operator's manual which came with my machine appears to be for the early model, with front-mounted carriage drive motor and handwheel operated spindle speeder. (like yours). I would happily swap my manual (original) for one appropriate to my chucker, which, I believe, was manufactured in 1980.