I have a vintage pen with a hairline crack in the section, which is causing ink to seep out. It's an old Caran d'ache Madison, and being second hand I don't have a guarantee. The nib is quite lovely - so I'd like to ge thte pen into a conditin so that I don't get inky fingers everytime I use it. I can't find a replacement section. So, what would anyone suggest? I've noticed the part on repairing cracksin MBs, but this is hard plastic, not celloid.