I’d have published this yesterday, except then I wouldn’t have been able to tell my wife she had the one and only one in existence…
Materials: 1 sheet of medium maple ply (which leaves a lot of scrap, unfortunately), about 4" of the end of a sheet of clear acrylic, and about a 3" square of red acrylic. And glue.
There are 4 unique parts, A+B from the maple ply, C from clear acrylic, D from red acrylic. It needs 3x A, 2x B, 2x C, 1x D (D is two hearts).
The outside dimensions of A and B are identical. C fits inside of B, and is captured by an A on either side. The two D hearts go between the two clear pieces and move around freely. The parts stack as seen in this image and are simply aligned and glued together. The V of the heart is 90º so a simple alignment fixture can easily be made with some scrap wood or a couple of bricks even.
And here’s a partially exploded CAD shaded drawing of all the parts.
And here are the SVGs (which you ought to be able to save via a right click on the image), but without the text so you can add your own if you want…
Wood parts A (3x) and B (2x) cut red first.
Red Acrylic parts D (2x)
Clear Acrylic parts C (2x)