Hello James,
I found that building the frame myself gave me exactly what I wanted shape wise. I used 1.125" stainless tubing readily available from iron and steel manufacturers. I think I paid about $70 for enough tubing to make the frame. This was bent over a plywood pattern.
After that, starboard was mounted to the deck and cabin top for the canvas to mount to.
I then paid a professional to cover the frame with canvas. The result was something I'm very happy with.
The shape is very close to Dave Kings dodger which I shamelessly copied...., it is nicely proportioned and "fits the boat"