Villiers headlamp switch

[R]

Bit slow here, need something to git thungs movin agin ?

Anyone care to explain the Villiers headlamp switch ?
Waratah/Excelsior 125cc circa 1945

I thought it was a Miller, but new/replacement has a chrome ring around it.
And would be (slightly) too big to fit ??
What retains it - a large wire circlip ?

DIM/OFF/FULL
https://britcycle.com.au/wp-content/uploads/2025/04/Miller-Headlamp-Switch.jpg

[cardan]

I'm only slow because I'm spending too much time in the shed doing a 50-year service on my recent acquisition... the clue is that it has more grease points that any bike I've ever encountered.

Leon