Numrich gun parts has new extractors for these. The guns were made in Germany in the 1960's. Beware of the firing pin rebound spring. It gets lost quickly when you take the breechblock out.
Both the receiver and breachblock are made of a very soft aluminum alloy and are not much stronger than pot metal.
Poor extraction is common on these guns. They do have a very nice barrel attached to the rather dubious receiver.