It could very well have been a bare hull obtained thru US Molded Shapes or Industrial Shipping in Canada that a do-it-yourselfer finished at home. Andreas
The reference to Industrial Shipping in Canada reminded me of some info I read on a website about Yellow Jacket boats that were molded plywood. See the link below. While your hull shape does not appear the same as YJ's, I thought some of the history and distribution outlets might be helpful in your quest. Notably, Richard Cole was the marine architect for Industrial Shipping as well as many other famous boats. Also, Sears and Montgomery Ward both sold these type boats under their brand names. FYI, YJ's had fins on their later models. Good luck!
