Did it maybe get put inside something else? I once lost an antique Christmas ornament for four years. It was in with a box of bows and ribbon. I know it is a pain, but you may find yourself tearing the sewing room (and others) apart again. If it has not left the house, you know it is there. I would get systematic and actually make a list of the places you have lookes. Sounds goofy, I know, but it worked for me when lost something once.