I have the stone Stark house card and glass Stark power counters that were made available for redemption not long after the CCG started.
I also have an art print (of a Stark soldier) signed by George RR Martin that I won in a Game of Thrones ccg tournament many years ago. It is showing some signs of wear but is still a nice and, I imagine, fairly rare item.
All of these items are available for sale, either as a job lot or separately. I am based in the UK, but will keeping shipping as low as possible - probably not more than $5 to the US, for example.