The Japan Post Service announced that they will be released a stamp set commemorating the Giants' Championship season. Interested buyers will be able to pre-order the set from their local post offices.
The set itself includes ten 50yen stamps, a stamp holder, and a special plate. Each set will cost 3,300yen.
Pre-orders will be accepted through to the 30th and the stamp sets will be shipped out on January 18, 2010.
=== UPDATE 11/10 8:00pm JST
Here's an image of the set (via the Japan Post Service website):
A Nippon Ham Fighters version has been released as well.