Quoted from the page:
For shipping charges and
information about international orders, please use our shopping
cart system and click on the "Non-USA Destinations" link. Select
your country from the list for the proper shipping charges.
If your country is not on the list, send us an email and we'll look
into it.
Might not hurt to drop them an e-mail to inquire about the
possibility of shipping the plans to SG, if you're serious about
building the contraption! 