They are indeed available after a cutscene, although I don't remember exactly what triggers it. I think it was almost completing the Chronolex that triggers it. Just keep going into the shop and you should eventually get it.
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<--- Nodoka Miyazaki Fanboy
Still holding my breath for the other Marl Kingdom games.
My NIS(A) Game/Accomplishment list is located in my profile. (Warning: Possible Spoilers.)
