I am a fountain pen fan too! I usually stick with a cartridge, but I have one that has a converter I use with bottled ink. Perhaps one day I will be generous enough to allow my children to use them, but for now I hoard them for myself!
I'd very much enjoy writing on a chalkboard as a vintage supply, but I'd rather not introduce that much dust into a home I am in charge of cleaning. Whiteboard it is!