Expert Needed: Locate Verified 1898 Birth Record in Croatia/Serbia (Language Skills Required)

I am looking for the birth and/or baptismal record of my grandmother, who was a Roman Catholic ethnic German Croat born 1898-99 in the Kingdom of SCS -- either Croatia or Serbia. I have gathered limited information from US records (Ancestry, FamilySearch, family records) but need to access parish and municipal records in Croatia and Serbia. I can share the following upon engagement:

Grandmother's Name & Birthday
Possible birthplaces: Vrbiza, Vibice, Frbica, Urbia, Urbico
Father's name
Mother's name
Sibling information
US emigration information (ship manifest, Ells Island info, US naturalization)

Please let me know if this is a good fit for you.