Hello Richard,
As Casey mentioned in his post, the Port-A-Bote might be what you are looking for in terms of portability, size and flyfishing stability.
Take a look at my review here on FAOL:
http://flyanglersonline.com/prorevw/portabote.php
It is a V-hull, but when you stand up in it, you actually stand on one side of the keel, not straddling it. It is very stable for flycasting.
Cheers,
Richard in Plano TX