I have a 640 that I've been carrying for over 20yrs as an alternate weapon. It has a satin bead blasted finish but its been scratched up a little over time through general use. My question is how much should I pay to have it re-finished / blasted and what are the options available. I don't want to buy a bead blaster & a trip back to S&W may take too long. Mother's Mag polish will shine it up too much for me as well. I want to get the smoothed finish back before I retire in a few months. Kind of a new beginning.