Thanks for the additional photos, showing the rails and rocker. And, thanks for measuring the board.
The rails and rocker are exactly like the Maui Foil, as I suspected, being down railed from the tail up through the middle of the board. They then turn up as they approach the nose tip, creating a somewhat domed bottom in the nose. (By the way, this turned up nose rail with the domed bottom is something we first saw become a standard design feature on the Bing Pipeliners shaped by Dick Brewer, starting in February 1967.) There is also much more rocker in your board, like the Maui Foil, than the true-blue Aussie Foils of 1969 and early 1970.
Dimension-wise, your board is also like the Maui Foil, in that the nose and tail widths are the same, though yours is wider than the earlier Maui Foils. The widths on your board are the same as the Bing Glass Slipper model, which Bing designed and introduced at the same time that your board was made. The Slipper was shorter and the rails were turned down and met the flat bottom of the board with a hard edge, except in the nose where they continued to be turned up.
Your board could almost be considered an intermediate design that shares some design features of both the Maui Foil and the Glass Slipper.