In case you decide to stick with the character and find a motivation to go along with the plot:
which means now I'm on a quest for magical items my character doesn't even believe in.
Your character is a pirate. Aren't pirates interested in finding treasure?
Your character might not believe in magic powers. But your character might believe that there are gullible fools with too much money out there who will pay a fortune for these supposedly "magic" trinkets these superstitious scholars are looking for. They are useful tools to guide you to that booty.