Water fowl leg rings ?

I'm looking for a source of leg rings to go on my ten week old ducklings.
The rings need to stay on for life and obviously need to be comfortable with plenty of leg room.
I also need them to be all one colour, so that all the ducks that I've bred this year will be sporting the same colour jewellery.
Another requirement, is that the rings be individually numbered so that I can accurately make records of what came out of what in the brood pens and whose related to who.
Any ideas as to where I might be able to get them ?

The coloured vet wrap that you can see on a few of the ducks is me curing a condition that occasionally affects waterfowl called 'Angels Wing' A few days in their straight jacket and they recovered completely. :)