You can find the Future Floor Finish at the following,
Ace Hardware, Home Hardware, the DIY Store, and grocery stores like SM Super/Hypermart and Rustans.
Another alternatives is to use the "Johnson's Wipe and Shine" or Pledge. It has the same ingredients. I would suggest to try sampling first before applying to unused styrene sheet the effects or the reactions of the chemicals. And try to thin it, 25% alcohol and 75% Future.
In Singapore I used the Future and In Philippines, Johnson.