The International Oleander Society is in Galveston, TX. I have ordered cuttings from them in the past.

Here is a link that might be useful: International Oleander Society

If you are still looking for coral and yellow oleander I have some.
Regards,
Mickey

I'd be cautious selecting Oleanders. Here, in Southern California, they're all dying due to the Leaf Scorch disease. I hear the white ones are the most susceptible but who knows? Bound to travel to Vegas I'd think.

Did you get your oleander? I live in Arizona and we don't have any problem yet of dieing oleander that I have seen yet. I lost a bunch because they didn't get enough water in the winter.
I still have yellow and coral if you want some when it is warmer.
The yellow are Sorento from Monrovia Nursery and the coral are MRS. GEORGE ROEDING usely just called Mrs Roeding , that one goes back to the 1800's.
A good nursery should be able to order them for you.Now is not the time t be doing this however.
Mickey