Check Engine Light with Bank Codes on 2002 Infiniti QX4

The Check engine light comes on and when I had it checked, these are the codes that showed. Bank 1 - P0430 and Bank 2 - P0420

I heard it could mean either I have to replace the catalytic converters or the exhaust may be leaking. I'm live in CA. Do you know what the cost for repairing the leaks or replacing the cats would cost?

Asked by for the 2002 Infiniti QX4
these are long dollar items. i would plan on spending upwards to 1500-2000