Bought a Ironhorse Hollowpoint MTX for my girlfriend to ride a little while back that had some reducers and what looks like either a cane creek or fsa IS headset installed in it. I'd like to keep both, however the original owner no longer had the crown race or the shim up top that goes in the headset. Does anyone know how I can order just those parts, or do I pretty much just have to buy the same headset to get them?