From Duckman's WDCC website, it says this about the Mal piece:
- Walt Disney Collectors Society Members Only release-Villains Series for 1997
- Available to Society members by Special Order with Redemption Certificate.
Edition closed 09/15/97.
- Final edition size of 7,047 hand-numbered pieces including dealer displays.
- The first 3,000 members to order received a special edition lithograph (11" x 14") of Maleficent.
Actually, there shouldn't be an edition size on it since it was a Member's Only piece. As far as the 'b' is concerned, perhaps it really says "4756 of 7000". The other possibility is original 475 was broken on shipment and a backup sent with 475b as the replacement number??