Vienna State Opera website:
http://www.wiener-staatsoper.at (only in German). At the far right on the main page is a picture of the inside of the house - you can see where the good standing room is.
Current prices for standing room: Euro 3.50 for Parterre or Euro 2.00 for the top two tiers of the theatre, right at the sides.
The person sitting next to the Parterre standing room will have paid between 91 - 178 Euros.
I will be visiting Vienna, Prag and Budapest in October this year - if you get back before me please let me know if Vienna has changed, and what it's like in Budapest and Prague - I've never been to either city.
Audrey