FYI,the SA 5spd hub was the standard config before the 6spd setup,and the hub's made by the same folks that made the hub you have now.
but back then there were 2 indicator-shift chains out opposite axle ends , an entirely different hub.. 234 were closer together .
& then the 5star was made in England , now the Sturmey brand is owned and made by a new division of Sun Race , in Taiwan.