There is no code that says “catalytic converter failed.” Quite often replacing an oxygen sensor, or two, will fix the cat problem. You don’t want to spend $900 for nothing, do you? Make sure.
The factory cats don’t have “rarer” metals in them. All catalytic converters have the same metals. They wouldn’t work without them.
Having said that, there has to be some difference between a $900 dollar cat and a $150 cat. I’d say go factory or at least find something in between. Is the $150 cat a “universal fit?”