capt mac is referring to a different brand of boat that he own's called Tsunami. It's a CC like the 23sf. see this thread
http://www.classicseacraft.com/forum...=&Number=41298
took me a while to figure it out. also I think Potter sold the company in 1980 so it would be from 1969-1979 or 80 someone else correct me if I'm wrong?