Yes, off on a tangent, but that's half the fun, isn't it?

My point in mentioning that my dad's airplane was based on the Snowflake was that the plane in the picture might be something like that. Lots of guys would see what was working at the time and do their own take on it. The similarities I see are the general size, shape of the wing, shape of the rudder, cowled in glow (or spark) plug, clockwise flight and a general similarity of airfoil. The shape of the cowl, needle nose spinner, streamlined tail cone and apparent asymetrical wing are different, so I still think it's a Snowflake-based original.
The 151 mph flight I mentioned took place on June 11, 1949, so an airplane of that size and configuration would have been competitive. Also, John Stokes appears to be about my dad's age at that time, he was a WWII veteran and an engineering student in Indiana at the time. If he were still living, I'd ask him if he'd ever run across John at a contest.