Any help with the following would be appreciated.

Engine light coming on intermittently for months. Code is Catalytic
converter (bank 1, I think he said).

Can this be anything but the catalytic converter?

Dealer price for the part is about $1725.

It doesn't seem to be available as an after market item. The 49 state
(not Calif) models are just a few hundred dollars, but the California
one is something like six times more expensive.

Is there any way to do this properly at lower cost? Does anybody offer
a California approved part other than the dealer?

Thanks in advance,

Rick