USPS Priority Mail boxes (used) (Clear Lake City)

I have a number of used Priority mail boxes that can be reused. The labels will be removed as much as possible and they will still need postage to be used. I no longer need these as the business I am associated with now uses USPS Ground Advantage. I have ten of the 7x7x6 and one 11x8.5x5.5 and one 12x12x6 1/2