You won't have to buy a feed dog cover if your featherweight came with the Singer buttonholer. To make the Singer buttonhole attachment work, the feed dogs must be covered. Those old buttonholers (green plastic box) all came with a feed dog cover plate. As for a darning foot, a generic short shank darning foot will fit. My Janome darning foot will fit my featherweight so you may have everything you need to FM quilt with your featherweight without buying a thing.