Listed is one, genuine LUCAS PRS 3 combined light and ignition switch, complete with fixing clip and key.

4 screw terminals, tested and working. Original part, as fitted to many 50's 60's vehicles. Austin Healey Sprite, Morgan, Land Rover etc.

Not perfect, but serviceable. 

Barrel 41mm. dia. x Assy. 86mm. long.  

Part Nos. on Barrell. 31270F 10 62 

Good Luck, Thank you.