Chris:
In Brussels, Private Reserve is likely to be sold as Schmidt. If you can't find the Schmidt, please PM me. My sister worked in Brussels and still has contacts there. If you are interested, we may be able to get some to you.
Andy,
Thanks for the offer but I think I'll continue with Pelikan cartridges. For me they're the Private Reserve equivalents here: cheap and available. As for Private reserve cartridges in Belgium, I meant that I never seen them round here. But in Brussels one can find the Schmidt stuff (Rollerball refills...) in specialty shops.
@micah
I found out that some of the converters guys and gals use the converter for they want to change inks at will. If you could have some cartridges of different colors it would be easier (well it's my hope at least) to persuade your customer to abandon the cartridges and several bottles of inks apparatus.
Personnally (after a quite happy selling experience) I now carry cartridges in... violet and pink...:biggrin::biggrin::biggrin: