We have shipped to the Philippines many times.
With regard to Customs and Duties, the way the carrier will collect them from you will vary by the carrier and sometimes even by the region of your country. In most cases the carrier will call or email you after it has cleared customs to inform you of the amount due and then try to collect that amount before they will deliver. Another common process that many carriers will do, and more sore when the amount is low, is that they may attempt to collect the full amount due at the time of delivery without first contacting you.
If you want to know for sure how they will proceed, please reach out to the carrier you plan to ship by and ask them how they handle Customs payments in your area.