I have no idea of the exchange rate, but what you describe wouldn't be a rip-off at a walk-in, actual store. That is to say, US$60 wouldn't be too bad. However, you can probably find it online for somewhere in the neighborhood of US$35.
If I'm not mistaken, Singapore has some pretty strict rules on them, so you may want to ask around... Shipments from the US may get stopped at customs...