Hi - I promised someone that I would pop a few pics of the willow pattern bobbin on here (from early 1990's!!) managed to find it in the 2nd bobbin case I looked in which was great as I would have had to go through at least 8!
You can click on the pics and they will enlarge. It was quite hard to photograph because of the flash and the satin varnish on the bobbin!!! :-D
But it will give you an idea :-D