I don't think it's so old.... look at the alloy bracket for the rear mudguard.
I worked in Comrade Cycles bike factory in Darlaston in the late 70s where they made a bike like that, without the basket, which, unbelievably, they exported to India and China. They were damned heavy to lift into the backs of trucks though; we hated loading them.
A decade or so earlier my pal and I fished an original baker's bike frame out of the river Thame with a hook on a string. We discovered that it had a hole in the RH chainstay where for years the crank had been hitting the stay, so i took it to the village garage where the mechanic did a beautiful brazed repair for me for free. We cut off the basket and fitted it with a rear wheel with Sturmey-Archer hub, ape hanger bars and a small front wheel "donated" from my little brother's Triang bike. It had a dynamo and a huge chrome headlamp and I actually built a chopper seat out of bent tubing and wood. It looked as cool as anything. We moved to Newcastle and the chopper and two other bikes were stolen one Sunday from the cellar under our dining room while we ate Sunday lunch above. The two street bikes turned up on the town moor with their brakes cut but I never got my beloved chopper back. Sadly no photo exists of this amazing bike.