If you just want a flint on your SAK, try this. Get one of the Victorinox corkscrew insets with the small eye glass screwdriver in it. Insert the corkscrew insert backwards into the knife's cork screw so the screwdriver blade faces out. Grab the screwdriver blade with a pair of pliers and pull it out. Take a Spark-Lite plastic striker and saw off the end opposite the spark wheel and remove the spring and round flint. Adjust the size of the hole with a drill bit and take the flint and glue it into the corkscrew insert. Ounce the glue has set, use the file to rub angaist the flint to make sparks. Be carfull as the flint is not terrible strong.