I suggest you get it from online optical stores where the prices are much lower than in the brick-and-mortar optical stores. But generally speaking, it will take about 1 week or even more to get it cuz the glasses may be shipped from the overseas countries. If you aren't in urgent need of it I think this may be a good way.
As for eye exam, I just found this link http://www.whatclinic.com/eye-clinics/philippines/eye-exam for you. Hope this will be helpful.