As one of its daily deals, Groupon offers Mason Row Self-Inking Stamper for $25 with free shipping. That's $21 off list and the lowest total price we could find. It includes an additional color cartridge and features a custom design on an engraved rubber die. Deal ends January 13.
It also offers the Mason Row Self-Inking Trio Stamper for $30 with free shipping. That's $20 off list and the lowest total price we could find. It features one stamp with three interchangeable custom stamp designs in different colors.