Where to Buy Styrofoam Sheets and Boxes in Phnom Penh

I have been living in Phnom Penh for 11 years but I still do not know where to buy or find lots of things. It's obvious, many things are not yet available here. Some are available; where to find them is the question.

In case you are wondering where to buy Styrofoam sheets and boxes in Phnom Penh, Cambodia, you will find all kinds of sizes in front of the Olympic Stadium by Sihanouk Blvd or St. 284 not far from the Canadia Bank, between St. 199 and 190.

Here is a map I cut out for you.