In a nutshell, they are expensive!, and pretty complicated, especially if you need 'control' (automation) on them for large batch, small parts like your doing.
If you post some sketchs of the parts (where is the raised crown , end? middle? ) someone may suggest a good way of making them thats 'scaleable' for production volume.
From your description so far it sounds like a punch operation, and then a dedicated, small custom axial / radial ring roller might be the most economical way forward.
This thread is getting very close to 'work' (day job) for me now, so ill bow out
good luck with the project