Alternatively, you can try massage centers, saunas and spas. Perhaps, try asking derm clinics. I recently bought citronella oil from my dermatologist at his clinic. He also sells other oils, like lavender. He mixes the oils himself and the these are quite affordable. I bought the citronella oil for 90 pesos and the size of the bottle was 90 ml, if I remember correctly.
Where you can buy lavender essential oil in the Philippines
I get my essential oils from Casa de Lorenzo Oils and Aromatics as they have real essential oils.