Wanted Simplex downtube double lever clamp

[Deanthebean]

Hello I'm after a Simplex double downtube gear levers clamp 28.6 tubing its for my daughters bike the current clamp has broken. We've been on Ebay but the prices wanted are silly plus most sellers are not sure on the clamp diameter. I'm sure someone has one in their spares. It's Prestige but any one will do please it's just that the retaining bolt is some sort of odd French thread.

 

[Southwestslacker1]

Think I’ve got something, definitely old, not sure on brand. I’ll have a rummage.