Many times the extractor can be bent slightly and replaced with a new rivet and it will work. The problem can be crap behind/around the extractor, and extractor that doesn't come out enough to begin with (the bending thing fixes that), or there are burrs in the notch the extractor sits in. Extractors and rivets are pretty cheap so I'd buy 2 extractors and 5 rivets. I personally just turned a part on the lathe to go in the bolt face and grabbed it in the vise to pound the rivet in.