Finally a photo, many thanks Gizmo.
I cheated & just took a photo of an album page as some of these photo's negs are a bit hard to find...
Hope you can see enough!
There is a story connected with this first yacht, in that the local hang glider guys at the time heard about me sailing through Dad, and came & had a sail when I had the yacht sailing at the Morphet Vale high school oval. I took a couple of them for a screaming run across the oval then- Bang! a stay went & we copped the mast, sail etc. as often happened, but it didn't seem to bother them at all.
This had happened so often that we had actually modified the yacht by using a universal joint at the mast base so the rig would suffer less damagewhen it fell over!

When it happened, you were also able to lie down on the bench seat & avoid having all the paraphenalia hitting you...
The upshot of the hang glider visit turned out to be that when they went to the US for a competition, they came across a Manta landyacht built by the Manta hanglider manufacturer, and brought a number of the little yachts back to Adelaide.
This sparked a spin-off copy by Free Flight hang gliders here in Adelaide & these yachts triggered renewed interest both here and also in Safety Bay WA, where Pat Coffee kicked the sport off over there with them.