Subsequent to above….
I have examined the machine carefully. The maker's plate does not carry the serial number, certainly not legibly, but I will look again.
I could find no sign of another label having been removed anywhere.
It is evident that whoever painted the shaper white, did not remove the maker's plate; just wiped stray paint off it afterwards.
The sizeable number "12" stamped a bit obbly-eyed on the faced area just above the vertical shears, has nothing to say what it means, and a 2-digit number seems out of kilter with the list on 'lathes.co.', starting at 469.
So still a puzzle. I may remove the name-plate (seems to be held by round-headed screws, not drive rivets) to examine it in better light. It's not very accessible in place.