Just found this in Splash magazine and also Planet Philippines
White Mobile (new one on me that's why I'm sharing)
http://www.whitemobile.com/

White mobile cheap call to Philippines (and other)

I though it was worth getting a free SIM and the call costs seem OK
I'm always happy to get free SIM's with good call prices.

Anyway, take a look if it suits you get you SIM
(I think you'll need to cut one down for micro-sim)

Enjoy