I forgot old "come in the mail" AOL and other sample CDs
we used to get so many of, true circles and have a smaller circle inside. In my stash is also half of a plastic egg, from when panty hose came in plastic eggs, and like someone else said, old and new cookie cutters for applique patterns, they last forever.
And if you can get the Plexiglass square, you can use a non permanent marker to mark around the pattern you want to "fussy cut" lots of duplicates for that pattern. Just find the match, hold the square over it and cut around it. Or mark around it for scissor cutting.