Here is a batch of Franklin-Christoph nibs ground by nibmaster Matthew Chen.
In this collection we have in polished steel a BBCI. A Raven steel BCI, and MCI.
Only about a dozen of each, while supplies last. $65.
These are sold as complete nib units including metal nib, feed, and housing. Please review our recommended method video for removing and replacing these nibs from pens to keep them in alignment.