Just another option and how they look on an early bike.
Before anyone mentions, yeah, the bar ends are fugly.
[You must be registered and logged in to see this image.]These are Pro Taper Pastrana FMX ,at 800mm wide, 10mm narrower than the stock bar.
They're a tad taller and a slightly different rise/pullback.
They can be cut narrower still, 19mm a side by my first attempt.
Clutch master cylinder barely clears on the left side.
Pro Taper have a great site for comparisons.
[You must be registered and logged in to see this link.]'Course, Renthal prolly has something very similar, if you want to stay Brit.
Please show us your progress, when you've made the change.