Kinda strange, I would put it in the 70s too because of the brakes but the 70s fastbacks were solid color. The striping isn't right IMHO> That would be on a standard Commando not the fastback.
It is very easy to put the cafe seat and tail on any of them. They interchanged if my diminished capacity as an old fart serves me right. That (goodwood)green is common from the late 60s up. Then of course Triumph was the last one standing.
