I had to look this up but it appears to be a "Indian Star" variation. Ismac's has a nice collection of decal examples:
http://www.ismacs.net/singer_sewing_...ic-decals.html
though I did not notice the Star and Sphinx. They'd probably be interested in a picture of your machine. I see part of your serial number AG... so your 1941 date is probably correct. Very unusual and Thanks.
Jon