Then why don't you make something like a Quest,that if you have 2 Kiel_Cards you can upgrade them to a Kiel Card v 2.
Something like this :
// Normal Kiel Card
4403,Kiel_Card, Kiel-D-01 Card, 6,20,, 10,,,,,,,, 769,,,,,{ bonus bDelayRate, -15; },{},{}
// Custom Kiel Cards
ITEMID,Kiel_Card_v2, Kiel-D-01 Card v2, 6,20,, 10,,,,,,,, 769,,,,,{ bonus bDelayRate, -30; },{},{}
ITEMID,Kiel_Card_v3, Kiel-D-01 Card v3, 6,20,, 10,,,,,,,, 769,,,,,{ bonus bDelayRate, -45; },{},{}
ITEMID,Kiel_Card_v4, Kiel-D-01 Card v4, 6,20,, 10,,,,,,,, 769,,,,,{ bonus bDelayRate, -60; },{},{}
Just an idea.