That's actually the earliest maple stock 10/22 I've heard of. The previous early # I had noted was 232-54643.
Ruger using maple at the time, instead of birch, was just a matter of economics. At the time, Ruger just happened to get a good deal on a big batch of maple blanks, so used those instead.
To get one tiger striped like in the picture, was luck of the draw!
Chet15