The Princess Statue is the only decoration that can only be aquired trough a Clan's Goal.
Each donation is of atleast 1.000.000 gold, which makes it the most expensive Clan Goal even tough the Princess Statue is just a decoration with no kind of buff or benefit to your kingdom. The only benefit of unlocking it is so when other players visit your base they will know you are on a strong Clan with members that posess the resources to complete the hardest to achieve goal.