dia comp.... tektro.... they're all over. basically any schwinn three speed had them back in the day.
sorry to you all but i live in the states and can't really help you (with my bucket of levers).... truth be told when ever i do a bike for someone the first thing i do is shit can those things for something like this.
Ugly M8. I'm an unapologetic aesthete, looks are important to me. Anyway, this is LONDON FGSS, so fuck off.