RockAuto.
AutoZone.
Advance.
Whoever is near you.
It's a bring them the core and you have it rebuilt by Cardone.
RockAuto doesn't need the core first but charges you for the core and refunds it to you when you send back the core. Don't even bother. The shipping is almost the core charge. Keep it and sell it on ebay with "Condition: unknown. No returns"