A very nice find by our new forum member sneakyduck!
This set was NEVER offered for sale in the shops. It was put together for an extremely limited edition set for competition prizes. As a result, these are in extremely limited numbers worldwide.
Maybe if you’re interested in this limited edition, you should check this Nintendo Power Special Collector’s Edition SIGNED by the CREATORS of Pokemon Diamond and Pokemon Pearl.
These were used to reproduce the artwork in high quality, for promotion on catalogs etc.