IMO, those Stronglight roller bearing headsets are the best threaded headsets ever made. They combined durability, lightness, and affordability in a way that has never been matched. If your headset has plastic cups, it's B-10 rather than an A-9. The conical metal pieces are the races on which the rollers run. They are intended to "float" inside the cups to accommodate for minor misalignment. Grease them up, and the roller assemblies, re-install and it should be good for anther couple decades.
N.B. as an experiment, in 1988 I installed an A-9 headset on my commuter bike and rode it for twenty years with zero maintenance. I opened it up in 2008 to see how it was holding up, and only found some slight discoloration on the lower stack races. I reassembled it, putting the former lower stack rollers and races in the upper stack, and vice-versa, and will check on it again in 2028.
Last edited by JohnDThompson; 12-02-19 at 02:52 PM.