You can undo and re-knit the top of a stocking especially if it's a hand knit. To re-knit, you need only come close to the original stitches per inch (gauge) since it's at the very top of the stocking. You can either knit the name in (see Fair Isle video under Free Videos tab at the top of the page, Advanced Techs) or use duplicate stitch to embroider the name on a plain background (
video). There are simple and fancy charts for the letters (
here for example) or you could graph out your own letters.