(15usd + 11usd (1st 500g) + 2.85usd (subsequent 500g if more ppl buy)) x 1.3 (credit card exchange rate)
so if more ppl share, the shipping price can be lowered. Shipping time is about 1-2weeks.
However I know amazon packed their stuff in big boxes which may result in more exp shipping.
Here is a rough guide.
1 item - Sgd$33.8
2 items - Sgd$21.93
3 items - Sgd$20.56
*Disclaimer: This is a rough estimation and may not be the exact price. (fuel surcharge + insurance not included in the price but shouldn't cost much.)