@bundled options: normally only SHDSL can be bundled. as Stefan Hedenig explained, SHDSL is not available in Heiligenkreuz. so no bundled SHDSL either. there are very few companies that also offer bundled ADSL. you could contact a sales-rep from ascus
http://www.ascus-telecom.com/ or
http://www.ascus.at for an offer. but you can't expect miracles from bundled adsl given the distance between your location and the CO.
the other option (if you don't want to go for fiber or radio) would be to contact A1 (telekom austria) and ask them under which conditions they would install SHDSL equipment in Heiligenkreuz. there again you should try to contact a sales-rep and not just the holine. and your organisation should be willing to take a long-term contract because SHDSL equipment is expensive and A1 won't be willing to make the investment and then let you go after a year or two.
on the long run (and if your organisation wants to stay at the location) fiber is probably the best solution.
if you are not sure about the long-term usage, I'd go for radio.