I believe this to be a Cartridge S.A. Blank .303-inch L Mark VII, based solely on the year (not the repurposed Mk VII case). It has a yellow stained wooden spitzer bullet. I haven’t weighed it, as my batteries are dead in my scales!
I’m curious as to the meaning of the star. On Australian drill rounds, such a star indicated that they were for the Navy. Could this be the same here?