my name is Erich Besau and I'm doing research in ancestry too, especially in Vienna, Weinviertel (northeast of Vienna) and south moravia - so the parts your family comes from.
Hirschstetten is now a part of Vienna ( since 1904 http://de.wikipedia.org/wiki/Hirschstetten
Breitstetten: a small village east of Vienna, now part of Leopoldsdorf (http://de.wikipedia.org/wiki/Breitstetten
Because of data protection law it is not easy to get records of the last 100 years, but if you can give me some more details, I can do a research.
Best regards from Vienna