Welcome to the forum.
I'm not sure who has control over Alan Payne's designs, but this would be the first place to look. Columbia had a factory fire in 1991 that likely destroyed any on site paperwork, though I'm speculating. I remember the fire and they lost a lot of stuff, including their molds.
Additionally, you can get a 3D laser scan of your boat, that would create a "point cloud" that can be imported into modeling software or ACad. This would let you have a very accurate set of lines of what you have.