I really like the pre-Raleigh Hercules (and other BCCI bikes- BSA and Phillips, especially)- I'm a big fan of their workmanship. There was a reason Hercules were neck-and-neck with Raleigh for number one bicycle maker in the Empire for so long.
The headbadge is the real giveaway- I've been told that all of the "Birmingham" marked Hercules headbadges were replaced with "Nottingham" ones by Sept. 1960.
Please post pictures as you get the restoration underway.