Cambodia Token/Amulet

This site does not give much information, but still some. Scroll down to the bottom of the section labeled Medals, Decorations, Amulets and you should see it (called Silver Amulets). It shows there are nine version, and you can see them all by clicking on the picture. Yours appears to be M402, but the site says that version is 40 millimeters.

I did send the pictures to the link and I had this reply:
"Little is known about these Cambodian pieces - or at least I could find out nothing years ago when I wrote them up. The symbols remind me of the Pyu-Mon-Dvaravati coinage and they could be simple decoration derived from those series - only a guess. Sometimes with charms from Asia, the makers don't really have any serious intent or knowledge, they just use imagery calculated to impress someone who might want to buy the piece for its supposed powers."