4 People Pedal Boats For Sale How Do I Make A Pedal Boat?

How do i make a pedal boat? - 4 people pedal boats for sale

Hello, I want to find the pedal a design picture below is a two-seater, but I need to know about materials and how would you proceed to long to about 2 feet, please help.
http://images116.fotki.com/v700/photos/4/41513/2976629/DAF_BathOSub_2-vi.jpg?1136775891