I'm late to the party. Regency RV has the National Traveler Class B RV's with 7 ft high ceiling.
Interior Ceiling Height
6’2″ (Trek) / 6’2″ – 7’4″ (Tour) / 7’4″ (Explore)
Although I'm 5'11", the extra height allows additional cabinets on the top of the RV. Check it out.
I'm looking at the new Panoramic RV. The National Traveler Explore is the closest that sleeps 4 in the Class B RV with European Bunk. It's amazing if it works. No actual reviews in the wild though.