If you want to play Galaxian 3 there are a few options. If you were at the Osaka Gardening expo between April and September 1990 you could have played the 28 player version before it was quickly dismantled. After that you could have played the downgraded six player version. 3 of those units still exist. One is in a mall in New Hampshire and hasn't worked for several years, one is in the private collection of a mentally ill Swedish man who charges people money to enter his house and take pictures of the machine but doesn't let anyone play it, and the third is still in Osaka Japan. Down from that is the PS1 port which isn't even worth discussing. Down from there even maybe it works in MAME. Who cares.