Advice for Northern Italy Sterzing-Vipiteno

[Effendi]

You cannot buy an Italian sim in Germany, you have to be in Italy, of course.
Vipiteno/Sterzing is not such a small town, there should be at least one official shop for the 4 operators and surely some multi-brand shop. No problems to buy a sim-card there.
Of course it's better to make a manual selection of the network since if you leave it automatic you could use an Austrian network, spending a lot of money in roaming charges...