The total cost of shipping a nerf gun from the states can vary quite abit based on which model you are looking at. This is due to the different sizes of the product boxes and the various promos that run from time to time.
For example, a popular nerf gun like the Longshot (its box is one of the biggest), the USA to Singapore shipping cost (via vPost) works out to around S$80. Currently if you pay that shipping charge by UOB credit card you can get a 20% discount, so lets count it as around S$64.
The promo price and domestic shipping of a Nerf Longshot from Amazon.com is currently USD$29.99... or approx S$46. Therefore in this example, a Longshot would currently cost you around S$110+ in total to get from the states.
Note that I have not yet added in vPost's additional base shipping charge of S$13.24 if you are only shipping just that 1 item. If possible, its always a good idea to group and ship more items to spread out the base shipping cost.
Also note that the shipping charges i mention above is an estimate, because you wouldn't know exactly what size of the delivery box the packer uses. The delivery box can sometimes be 20%-30% bigger than the actual Nerf gun's box and you could end up having to pay even higher shipping charges 'cos they calculate by volumetric dimensions of the delivery box (not just by actual weight).
Here is a more detailed guide and some money saving tips:
http://forums.hardwarezone.com.sg/showpost.php?p=32893837&postcount=95

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