Cheap International Direct Mailing Service?

Hello,

Does anyone in here know of a international direct mailing service
(that print, pack and send letters worldwide)?

I want to send a standard direct mail promotional letter to a large customer base of 10.000+ people.

In my country the costs for ONE stamp is: $1,3
A A4 letter costs: $0,17
Printing of the letter costs: $0,17
ONE envelope costs: $1,5
Total expense for ONE letter sent = $3,14 !!!

I need to get that cost way down!

I think I've seen (a long time ago) that US based international direct mailing service does all this for a much lower fee.

Tips, anyone?

Thanks.