Shopping via internet

For my wedding,
I've shopped a lot on the internet,
try to get deals and unique items.
Last week, I've ordered envelopes for our invitations.
Not very cheap cheap deal,
but I really cannot find where locally to buy just the envelopes.
Business No. 10 envelope, only that it's not white and it opens on the end.
Cost is around $0.35 each including shipping.
They arrived in 7 days, on time, not bad.
Except that: the custom charged me $55 for duty!!!!!
Now the cost per envelope -> $0.50
sigh........