Hi Jason,
It's probably #9960, since there isn't a #0266.
Bing's records stop at board #8411 in 1971, and then the numbers jump around some through the 1970s. I have Bing Swallowtail, which came out in 1973, and it's #9959. So, your "short board" was probably made then. There are Bing ads in Surfer magazine from 1972 and 1973 that show good examples of boards like yours, especially the Surfer July 1972 ad.
If you haven't already, you should spring for a copy of Bing's book, maybe as a present for your good 'ol dad, or for yourself. The whole story and history of Bing Surfboards is in there, along with a lot of pictures of great looking boards.
Tom |