Why would you even care, your engines are 2003 and so your boat is exempt unless the boat is a 2010 model with a 2010 hull number.
Yes, the 2009-2010 496 Mercruisers are not avialble for sale in California starting back in August 2009 and Merc will only sell the new Merc 502 Mag and HO's in California with the catalytic converter exhaust systems, that meet CARB requirements.
Have fun with your 2003 engines and if you want to add more performance just contact us here at Raylar and we can help with your upgrades or power addtion needs when the time is right.
Best Regards,
Ray @ Raylar