Mariela,
The very first Galician Ruthenians/Ukrainians to settle in Argentina
were 12 families, who arrived August 27, 1897. The author only listed following 6 surnames: Dutki, Mucia, Opykhanoho, Pysmenoho, Wynnyk and Zlizloho. They came through Brasil. According to the article I read, all came from the same district called Buchanivsky (Bucniow > Tarnipol > Galicia > Austro-Hungarian Émpire until 1919). Today the district does not exist and the town of Butzhniv (Буцнів) is in the Ternopilskij raion/district > Ternopilska oblast/region.
There were five villages that belonged to the Bucniow township:
Pochapyntsi, Loshniv, Ostaltsi, Kleschava and Slavtse.
You mentioned that your ancestral town started with the
letter P???
Pochapyntsi Greek Catholic residents used the filial church in Dragonowka/Drahanivka. LDS has filmed old church records,
if you might be interested, I can provide you the information.
Boris makes a good suggestion. You should contact your
same surname relatives and find out what they know. You