Actually I searched for Ogon here and couldn't find anyone selling it, but looked in the RHS Plant finder and found one nursery which doesn't necessarily have the plants listed. They do have a very good selection and I was going to order from them one year but they only do mail order over winter, and cut off early when I wanted to order as the plants were growing!
I never did order from them, but now might look into it this autumn.
Do you know what sort of conditions it likes? I have sandy soil with not a lot of sun, and very little heat too.
I would have thought yours would be showing by now if it was still in this world.