I would look up local roasters and see who sells 5lb bags (if I was making for 30 people it would be 2lbs of coffee so if they have 2lbs get that but no one near me sells that, so get a bean you like and use it for yourself for a while) just get their flagship bean.
Local gets you no shipping costs and no shipping time.
But if I was in the middle of nowhere I'd get this: https://www.stumptowncoffee.com/products/hair-bender?variant=40006908936360