I guess there is another rose called COCasun. I must have it wrong on my list. Sorry

I bought this rose from Sequoia Nursery in Visalia CA in 2002. They identified it as COCasun by Cocker in 1981.

From the Vintage Gardens web site: Very double flowers of sunflower yellow, petals quilled in long rays from a tight center, almost an old-fashioned effect but unique.