I realize this is picking up a thread from a three and a half years ago, but for the sake of (hopefully) clarifying the origins of some Royce Union-badged three speeds, I have one that is similar to the OP's, but is a drop (step-through) frame, in blue with white head tube, the caliper brakes are flat steel and unmarked, and the front hub has an oil port covered with a clip). It has the same graphics (the word obscured by wear on the OP's lower head tube would be "SAFETY").
I think mine's a '62, based on the Sturmey serial number AW-62-7 (oddly, the thumb shifter is a SunTour, but it looks like a later replacement). The frame serial number (stamped at the top of the seat tube) is 34569 (with N under it, and an S just below and to the left of the N). Is that not Raleigh? Bike has the same Raleigh style dropouts and chain ring (marked with Raleigh logo), cottered cranks lack Raleigh logo but are stamped "N". No marks on brake levers or stem. Front wheel is stamped Dunlop 26 x 1 3/8 Made in England", and rear wheel is stamped 1 3/8 R N F (what is that?) Came with the same brutal Wrights saddle.