These jackets were used by the East German "Kampfgruppen der Arbeitsklasse" (Fighting groups of the working class). The KdA was a paramilitary organization under the control of the Central Committee of the communist party from 1953 to 1989. 

The jacket you receive will not have the striped rank insignia on the right shoulder as in the photo. The pocket flaps on the sleeves may have covered or exposed buttons.