So is the ejector or "extractor" missing? The links I gave you is for the ejector parts because that is what you identied as the problem. If you want to replace the "extractor" then you'll need these parts:

Actual extractor
http://www.midwayusa.com/viewProduct...tNumber=107108

The "ball bearing" but is called the Detent ball
http://www.midwayusa.com/viewProduct...tNumber=149221

The spring incase you need it.
http://www.midwayusa.com/viewProduct...er=444465'

Hope this helps.