I may have designed these paddles about 15 years ago but now I have the first photos.
The paddle plans used to cost $45 but they have been free for a couple of years now.
They are very detailed with step by step instructions on all aspects of the building. There is a plan for both a classic 8ft double from Herreshoff – but with simpler and stronger blades of laminated plywood – as well as a more modern double.
The shafts are classic tapers with the right proportion of stiffness and flex. The 
plans also show how to size the single paddles to match the height of the user.
The shafts are quite classic and the blades are slightly curved.
The two paddles shown here were made by the young men in the picture – a 15 year old and a 12 year old.
They are now building a canoe to go with the paddles. See here on the OZ woodwork forum
And here are the free plans for the paddles and 9ft oars.