I wouldn't risk sending things like that through the Philippines postal system, especially when they can see it's come from the UK, it may be opened (to see if contains money) and then thrown away. It's always best to send it by courier and the best one for anything like this I've found is Interparcel. If you use Interparcel it will actually be delivered by DHL and you can even track it on the DHL website, but it's much cheaper than dealing directly with DHL.
Iain.