Lens for power LED question

Hello,
I am looking for a lens to install on a power LED inteded for flash lightning for cmos camera(such as cree or luxeon).
I found some lenses for this porpuse, but they are all too large (20mm diameter).
Can anyone reccomend such a lens with smaller diameter (10mm~)?

Have you thought about using a light pipe or making your own out of high quality plastic

I thought about it but I would rather buy a lens, that will save me time on this project