I rounded the prices to whole dollars (if they were under x.50, I rounded them down, over x.50 rounded up). All of the prices are for new books. It's usually not worth trying to buy them used, unless the books are less than $3-5 each, because of shipping. Since all these books are new, it doesn't cost anything to have them shipped to me.
Shipping for you is whatever it actually costs (I'm sure I can reuse a box to ship to you). I'd guess the average weight of books is about 10oz (some are a little over 8oz, some a little over 11oz).
EDIT: I just found out Priority Mail International has a flat rate for boxes up to 20lbs! (Used to only be a flat rate for envelopes, and you can only fit 3-4 books in an envelope).
The flat-rate for a box is $37 (http://pe.usps.com/text/Imm/ps_027.htm#ep1633410), so even if it took 3 boxes to send everything, that would still be way cheaper than using the shipping calculator (http://ircalc.usps.gov/default.aspx?Mode=Intl_Single&CID=10378). Or, you can place separate orders instead of one gigantic order.
The only other thing I would recommend is insurance, which is $6 for $400 (knock off about $1 for each $100 of coverage). I haven't had any problems shipping items internationally, but it would absolutely suck if your shipment was the first to get lost or damaged. >_<
List of titles not printed yet:
Ka Shin Fu
Love Bus Stop
The Summit 01
The Tyrant Falls in Love 01
The Tyrant Falls in Love 02
Worthless Love 01
Kizuna: Bonds of Love 09 (This should be available for $11 soon)
Maiden Rose 01 (This should be available for $9 soon)
World's End (This should be available for $9 soon)