Black overprint "Republik Maluku Selatan" and bars.
A lot of falsifications ('flat' letter 'M', see picture) are known.
From 25/4/1950 (independent Republic of the South Moluccas) 对 05/11/1950 (capital Ambon in the hands of the Indonesian army). After that, stamps were issued by the government in exile for fundraising and propaganda (see cinderellas).