In 1921 this region fell under Polish domain. Prior to 1919, from late 18th century, this was Galicia>administered by ethnic Poles for the Austro-Hungarian Empire. In order to obtain her passport, the only papers your Grandmother had to provide the district/Gmina office was her birth certificate/Baptismal certificate. Her metrika would contain the basic vital info, like name and occupation of parents.
The surname you are researching is distinctly Polish, so you need to locate Roman Catholic Church in area.
http://halgal.com/
Obtaining Polish Records
http://www.rootsweb.com/~polwgw/Research.html#church
PolishRoots - Parish Records Index
http://www.polishroots.org/parishes/lubaczow.htm