i've just finished a build for my friend and am only now curious about the model and year of this frame. The serial NP6075953 suggests it is a Nottingham build from, i'm guessing, '66, since it has the threaded boss on the right fork blade and wrap around seat stays.
anyhow, i've grown fond of this frame because of the details which you just don't see nowadays. And I think this probably was even a low end bike back in the day.
some original parts were steel stem and drop bars, weinmann vanqueur 999 centerpulls, 27" wheels w/ low flange normandy flip flop hub and 10sp. gearing.
on to the pics: