Made by Victoria, BC-based Whitehall Rowing & Sail, the Oar Board consists of a fixed seat, a sliding footstop and oar supports – all in one carriage unit. It's simply strapped down to the deck of an existing board, reportedly in under five minutes. Because it's made of a mixture of polymer plastic and marine-grade powder-coated aluminum, it should be OK with salt water.
Whitehall has already sold out one hand-made run of the Oar Board, and has now turned to Indiegogo to finance larger-scale production. A pledge of US$949 will get you one (oars not included), when and if they're ready to row. If you want the company to throw in a pair of Dreher carbon fiber oars, be prepared to offer up $1,539.
You can see the Oar Board in action, in the video below.