Gor-gee-ous machine and cabinet! You are lucky to have such a loving and generous friend! I didn't even know the 15 came in a full rotary version. Cool beans!
Also, looked up the decals on ISMACS. It's called "Wings", but I don't know if anyone knows if that was the official name or the modern nickname (you know, like how the "Sphinx" decals where officially called "Memphis".) Link here:
http://ismacs.net/singer_sewing_mach...ic-decals.html your machine's are about half-way down the page.