I looked at a Mariner 39 (the ones built in NH, not the ones built in Asia, which are two different companies/designs) which had a massive athwartships berth in the aft cabin... must have been over 7' long. The headroom was really good too, but I didn't write down exactly how tall it was (I'm 6'1"). I did write down that I could barely stand up in the head, however, so that might be a dealbreaker for you. Awesome boat, I wish I could have bought it, since it's built like a tank, but the price was just too much.
1979 Gulfstar 37 Laissez Faire