Ah, gut aufgepasst. Danke für die Korrektur.

Thank you for the catch. I was looking at this page: https://museum.post.gov.tw/post/Postal_Museum/museum_en/index.jsp?ID=22

Which is out of date. The latest page https://museum.post.gov.tw/post/Postal_Museum/museum/north/map.jsp states that there is no fee.