It’s hard to give an exact figure. The final price depends on the skill and experience level of the technician when it comes to re-padding. It will also depend on whether the flute itself needs a complete re-pad or a minor one. You will only need to re-pad your flute if it starts to feel like the holes don’t seal enough when you play notes. The only way you can have an exact quote is to visit a shop as soon as you can.