brujones1,
If you are set on a flatbed, here is a site that sells stamped, formed pieces. I bought all the pieces and assembled my own flatbed for my 4400 truck. You can even order "round" corners to give the bed that authentic look. The parts are surprisingly reasonable, but shipping to you from California might make the cost prohibitive.
I am not sure what you had in mind, but I think a flatbed requires duals to make it look proper.
http://www.flemingmetal.com/ Stuart
