@ tonyf39 - Thanks for the offer but I currently have a bit of a manky one already on the wheel, so looking for something a bit nicer :)
thanks for the ebay links though.
I think two bike manufacturers went by the name Diamant, though I'm not entirely sure.
As far as I am aware there was also a Belgian manufacturer call Diamant, which I think your bike is.
below is a pic of my one: