I have an old Tiffany's Elsa Peretti fountain pen. It's a very thin lady's pen about 6 mm diam. with an asymmetrical teardrop at the end of the clip. Tiffany's hasn't sold these for a long time. I'm wondering if anyone has recommendations for a converter or suggestions for potential cartridges. The converter would be my first choice. Many thanks. Linda http://s3.amazonaws.com/bureau-of-trade/p/2012/12/03/charcoal-gray-enamel-fountain-pen-by-elsa-peretti-for-tiffany-co-640.jpg