There is also a bookshop on the island, which also houses a post office where you can send postcard greetings to friends. The bookshop offers Moomin books in several languages, postcards, stamps, and other delightful Moomin-themed bookshop items.

https://www.moominworld.fi/attractions/shopping/the-moomin-post-office-info-point-and-bookshop/