Ciao Miguel,
Likely just 2 days before is too late to find tickets, the good seats generally sell out on the first day and the "curve" or seats that are reserved for each of the team's fans on the ends are standing room only, those are generally available longer but who knows when.
I honestly don't know if there are agencies that buy a lot and then resell them, or if that is even allowed.
But you can still go downtown, go stand along the route the parade in costume takes to Piazza Santa Croce and enjoy the festive atmosphere. You can stick around the piazza and soak in the atmosphere of the game for a bit, if there is space there might be a chance to get in.
The game is aired on local TVs and that gives you a much better view, if you want to watch it.
As far as Google Maps go, the marker on the map is wrong so it is very possible someone went by and signaled it to Google, who then marked it as permanently closed because the office is not at that location. I checked their website, their headquarters are there and that's the address on their website, they have many points of sale across the city for other events but for Calcio Storico you can only get them there. I've been, there's a big crowd to buy tickets and you get numbers first, to then manage the crowd. It's getting a number that's the mess, then once the numbers are all handed out the part is waiting to see
Hoki Arena if you still get seats by the time you go in.
