Unfortunately, I can only help in narrowing down the address. When you look at the word before Gratz, i.e., the word you transcribed as Gas????, it is "Gösting" which is the 13th district of Graz. Arnold Schwarzenegger grew up in Gösting. Well, perhaps just a little bit outside Gösting and the city borders of Graz.

Gösting was also my home for a few years. Still, I cannot read the street name or interpret it. The name seems to start with a number or initials followed by Josef, while the end of the name could be -steiner. This must be a long road as the house number 274 is rarely reached in towns or cities of Austria.

Perhaps the name of the street was changed after WW 2.

Austria (including Graz) was part of Germany (Hitler's 3rd Reich) from 1938 till 1945.