Water got on the wires to the outside central air unit, it sparked and then shut off. Is this repairable?

More than likely YES but you will need a knowledgeable person to track down the short circuit and make the repairs. Naturally drying out the items that got wet will be part of the repair.

Ahh...
Which wires?
What shut off, the breaker?
Why were the wires on the outside unit exposed?
Most likely repairable... keep the wiring dry.