Hello Dakers and welcome to Just answer.com, Super mechanic here. The catalytic converter is below the expected threshold. You could replace it yourself if you get the OE from the manufacturer but it would be more cost efficient and a whole lot easier to have an after market cat. installed by an exhaust specialty shop. They normally buy replacement exhaust components in bulk and they can replace them for much less than we can even purchase them for.
If the federally mandated emissions warranty does not apply to that vehicle. I would check with the dealer and see if they are obligated to repair it at no cost to you.