Feel free to use whatever you want!
The Drocca's Empire was a nation in an old campaign I DM'ed.
It was an arabian-like emirate focused on astrology and numerology that fell under my player's armies.
Droccans were obsessed by numbers, and the number seven was the most important of all. They had seven provincies, seven castes, a pantheon of seven deities and other similar thing I don't remember right now.
If you want I can look for my notes on that caimpaign for you :)