(Yes, there are still some machines in operation)http://www.galaxian3.com/~karin/g3list/g3slist_en.html
The Galaxian Theater located at Minolta Tower Centre was said to have vanished before 2003/07/25. Not confirmed what kind of Galaxian3 machine it was, may it be the 6-player arcade, or the 16/28-player attraction.
The page details where the arcade/attraction was eliminated. Out of all four 16-player attractions, however, at least two (unless the Chinese CYBER STATION and TOM'S CITY are the same model) 16-player version made it outside of Japan, in the Republic of China at CYBER STATION, and at TOM'S CITY, the latter being evidenced by these two photos below (Source from Kei8774, also seen in the 28-player thread).
Wow thank you for the information, that is interesting.
I do have an update.
The Galaxian 3 was physically located in the Minolta tower and not the building across the street.
As far as I know its a 6 player theater.
It was in the building with some virtual reality attractions that may have played doom and another game. There may have been other attractions in the building as well. The cybermind cafe was across the street and had one sit down virtuality pod and one stand up virtuality pod as I said before, this were not located in the tower themselves.
It was removed in 2001 when the building was renovated and a hotel was built on site. It was installed in 1995.
It was sold somewhere out of the Niagara falls area, as in its not sitting somewhere in Niagara falls Ontario in a warehouse at the present time, but it may have been in a warehouse in the past. I just talked to a major Niagara falls developer about this, I am very surprised they responded to me. Correction: I actually have no idea who or where it was sold to, so it could possibly be in the Niagara area, but I really have no idea at the moment, but it was definitely sold.
It is not at Dave & busters at Vaughan, Ontario as I just called them and talked to the manager. However the D&B at Vaughan ontario does still have a 6 player Galaxian 3 theater converted to Air Raid on the location as I write this right now but its not the same machine from Niagara.