If you log into the Faller website:
http://www.faller.de/App/WebObjects/XSeMIPS.woa/cms/page/pid.14.17/lg.en/Produkte.html
then select 'Track Gauges', then 'HO Selection', then 'Railway Stations Railway Buildings', then 'Railway Stations' you will find what you are looking for. There are also other types of railway buildings at the last step.
However most, if not all, of these buildings are based on German prototypes. These can be quite different to those found in Austria. German stations often are built of brick or stone, while Austrian stations, particularly rural ones were finished in yellow stucco plaster. There are a number of manufacturers of station buildings in Austria who specialise in producing models of Austrian prototypes or generic Austrian building types:
http://www.mbc-weiss.at/
http://www.h0-gebaeude-modellbau.at/produkte/Angebot___2608
Unfortunately their products tend to be somewhat more expensive. Hope this helps.