Cloth menstrual pads, a cheap and eco-friendly alternative to commercial menstrual pads.
Social Entreprise programs exist to create a chapter in your community, visit Days For Girls for more info.
In Siem Reap you can find more info with Purple Mango Wellness. They can faciliate workshops for your organization and give access to ready-made packs.
More info on Cloth Menstrual Pads on Wikipedia.