Yes, with two Pyramorphix-Puzzles you can make one Star of David and one Diamond. For the Diamond it´s better to change the color-design because the puzzle is originally always solved. In 1980 in east germany was such a puzzle produced under the name "Okki" with circle stickers. You can see it at my website
http://www.puzzle-shop.de under "Puzzle-Museum".
I have heart that U. Meffert will make a limited edition of the Star and the Diamond.