Li'l Snoozy would work, except it has a wet bath. My KZ has a dry bath, but (my 14RB at least) does not have a dedicated bed. Still, you could look at those floor plans.
What are you planning to tow with? A molded fiberglass trailer like Snoozy, Scamp, Casita or Parkliner are more aerodynamic than a Camplite or a stick built TT, which will save you 2-3 mpg and allow towing with a less powerful engine (possibly a less expensive vehicle). Also less potential leak points and reduced chance for water damage on those. A folding trailer like the A-frames can save even more, and some have bathrooms, but they are more skimpy on storage.
