Most Breslov seforim I have seen from the early 1900s are copies of Sichos/Shivchei HaRan arranged in different orders.
Emunas Uman - A collection of about 42 letters shared between Breslov elders, and about 19 correspondences between Rabbeinu z"l and Reb Nosson not printed elsewhere. First printed in 1966.
Neve Tzaddikim - Printed in 1969 by R' Nosson Tzvi Kenig z"l, compiler of Toras Nosson.
Sha'aris Yisroel - I believe this was also published by R' Nosson Tzvi Kenig.
Renat Tzion - A commentary on Likutei Moharan published in 1975.
Sha'aris Ya'akov -
Ohr Tzaddikim - A collection of letters shared between Breslov elders in Poland. Published in 1972.
Niemos Netzach - Collection of letters from Breslov elders compiled by R' Nosson Tzvi Kenig.