I have been searching far and wide for a website that sells those frames.
I know they come in 3 pieces, the frame, a piece in the middle to wrap your material around, and the backing.
But I cannot, for the life of me, find a manufacturer. If anyone has seen them somewhere other than etsy, please please help!
Making them will be the simple part. Just embroider something tiny, wrap your fabric around the middle piece or a cut a piece of cardboard that will fit perfectly inside and secure the fabric around it. Then you'd just close the prongs in the back and you're done!