For what it's worth, the Brampton SpeedySwitch like your bike has was commonly used on USA makes in the mid to late 1950s, on what were then called generically "English" bikes or, at least in the vernacular of Northern Indiana, "English racers." Essentially this meant a bike with squared off rather than curvaceous frame geometry, "skinny" tires and rims as opposed to the balloon tires then in vogue, and hand brakes rather than the New Departure coaster brake (without which my dear wife of 37 years is convinced a bicycle cannot possibly be ridden...at least by her!) And, of course, "multispeed" gearing, as exemplified by the Brampton which now seems almost comically primitive! When I had "graduated" from a balloon-tired "kiddie" Schwinn to a "full size" bike (meaning, as I recall, with 26" rims) around 1954, my new ride was a black Columbia with chrome fenders. "Rust belt" road and weather conditions (and lack of maintenance characteristic of a 9-year-old) soon led to rusty chrome and dull paint. By age 13 I had disassembled the entire bike and repainted the frame twice and tossed the fenders after banishing the last atom of chromium with rubbing compound in a misguided attempt to restore the luster of the bike's youth. Given my lack of finesse in painting and pinstriping (the latter being de rigeur on US bikes of the mid-50s) what I wound up with, by default, was something of a rat rod before rat rods were cool! A few rides during mud season sans fenders led to spattered clothing which slowed me down not in the least, but my mother was not amused. And so it was that Christmas, my birthday, and some spending money from odd jobs resulted in my being the proud owner of a new Columbia in 1959, at age 14. This had a candy apple red metallic finish, fenders included, and was to last me well into college days. It had, of course, the ubiquitous Brampton SpeedySwitch, exactly the same as my '54.
Has this helped to identify your bike? Probably not, other than suggesting its gear switch was popular in the 1950s, at least in the US. But I've a feeling that bicycle technology in Europe in those days was several years ahead of the US, out of necessity since bikes often served as everyday transportation for many adults there at that time. Anyhow, best of luck in your research.