Unfortunatly, if you want narrow and tall, there just isn't anything available in a modern tire. 27-28" is about all you're going to get and stay under a 7" tire width. Even then, the 5.5 rims may be too narrow. Also, with a modern radial, you'll have to go with a single peice wheel, tubeless tires do not work very well with multi peice wheels.
You might want to check with Coker or Denman, they may have a bias ply that will fit what you're looking for.
