Hardy Hibiscus (Syriacus, Rose/Swamp Mallow) with a true yellow flower

Hello to everyone out there and I hope you can help me.
I came across this seed exchange site and read about the seeds people have. I have searched my tail off looking for a true yellow flowered hardy hibiscus…I live in USDA zone 7-8. I can’t find “any” hardy hibiscus (syriacus, rose of sharon, swamp mallow or rose mallow hibiscus) that have a true deep yellow flower. Bullseye (Garden Tenders member) stated that they a hardy hibiscus and the flowers are yellow. I will glady swap seeds, provide extra stamps or whatever it takes to get some seeds or a plant start. I would like any information (names of yellow hibiscus or a nursery that sells/ships them) on a true yellow and or an orange flowered hardy hibiscus. I have a large book called “FLORA” “The Gardeners Bible” and it says there is a herbaceous hybrid hibiscus good in zones USDA 5-10 and it is called “Miss Kitty”. Again, I have searched the internet, asked internet people and inquired at my local nurseries
and have had no luck. Drop me an email at peschytz@hotmail.com Thanks so much!!!
PS. Even a true red (not burgundy/wine colored) flowered hardy hibiscus was very hard to find anywhere.