Age of my Perry Hub

[beastonabike]

I picked up a pre war Hercules and am having trouble nailing down the actual year. I know it can be tough to do just that but I thought I came close with some helpful information from a fellow board member. I checked the back of the brake arm from the Perry hub hoping it would reveal a year but it has just a single digit stamped into the metal or what looks like maybe 2 numbers. It has not made it any easier to find a conclusion to my question. How old is this bike?
The rims are far gone but some new wheels and some elbow grease this bike will have a much deserved second life.

Cheers,

Dave