I buy Naproxen Sodium tablets at the pharmacy in our local Lotus's store here in Udon Thani. You don't need a prescription but you do have to ask the pharmacist for it. It's called "Synflex" Naproxen sodium 275 mg , and manufactured in Thailand (under authority of Atnahs Pharma U.K. Ltd.) I buy the 60 tablet box (I think I paid around 680 baht), sold in a white box of 10 blister packs of 6 tablets, but I think you can also buy them by the individual blister pack.