I use aluminum rivet bodies pounded into the holes, ground down and polished even with the tang. you can use any drill with a 1/16 bit to drill through it easily as straight as you can. Hold the blade tang up with the bit thru the hole and see how straight the hole looks. Get the bit and saw back and forth until you get even wobble in all directions. A hand held tip drill helps! Your scales will dictate the rest. All pin holes in blades should be oversized IMO, at least to some degree. You can do the same with a lead fishing weight, split shot, or lead round bb/pellet gun shot. It does not need to be fancy, just something to take up some space in primarily Sheffield blades which were cast in and are often way to big and deformed when made. Not necessarily worn that way! Good luck!