MonksRule, I'm afraid you cannot get them back legitly, because you cannot return to Spellhold once you exit. However, I'm wondering if you have Yoshimo in your party, because that might solve your problem. I'm not going to spoil you unless you ask for it, because I don't know if this is your first game...
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Melusine, Archbabe of the Order of the Holy Flame and the Laughing Hyenas, &
Official Entertainer Elf of the BG2 Bar
Your voice is ambrosia