Not answering the question-as-asked, but this may interest you:
Up to the ALDMG v7, spellcasting services cost (usually rounded):
10 * spell_level**2 + one_time_cost / 10 + recurring_cost * 2
Beginning with ALDMG v8, spellcasting services cost:
I don't play AL, but reverse-engineering their original equation yielded something sensible that I've been using ever since. I'm just glad I looked into it before they started making up numbers that didn't follow a pattern.