I've been making badges for years.
Here's some history.
These are 5.25x4 inches. Nice size for a shoulder, I intended these as patches to be added to garments or bags.
My own dirty threads are stitched onto a single layer of light denim or medium-weight linen.
No iron-on gunk so you'll have to stitch them on yourself. I used 12wt cotton invisible stitches to turn the edges and it sinks right into the embroidery.
$24.00 each including postage inside the US. email me if you want one. Making them is so satisfying.
update soon