You have to buy an authentic and take those off from it. it doesn't have to be from the 90s exactly, cause CCM and Reebok use the same type/same material/same design since the early 90. So you can use those from the reebok edge as well.
As for sewing it--easy, get a 2" x 4" twill, sew 2 rectanges, and a cross, and that's it!!!