National Defence Order.

[CtahhR]

Here is the People's Republic Of Kampuchea's Order Of National Defence 1st Class. The award is very much in the Vietnamese style as Vietnam was the main influence on Kampuchea at the time.

[medals73]

The Order of National Defense / [sorry, I don't know the Khmer], type 2, 3rd class

Established in 1982 and awarded in three classes for services to national defense in the fight for liberty of the country.

Indochina Medals - People's Republic of Kampuchea - PRK03 National Defense Decoration

[CtahhR]

The Khmer is "ឥស្សរិយយស ការពារ មាតុភូមិ" I believe. The last word "Homeland" or "Nation" is rendered quite poorly and crushed horizontally making it almost unreadable with letters having accents above and below being misplaced.