The most well known supplier of pen kits is Penn State:
http://www.pennstateind.com/store/pe...n%20Pen&page=1
They have a number of different kits, and some of their more expensive (and often more gauche--unfortunately) have Schmidt nibs. You can often find 10% discount coupons, but I don't know how much shipping to Belgium would be. Your friend also might need the bushings and specifically sized drill bits which Penn State carries.
You can also search ebay for "fountain pen kit" and you should get some hits.
Bookmarks