It doesn't have to be $1000. Magnaflow cats are very popular... cut old one out and put this in place. I would constult with Magnaflow directly. Other brands use tiny cats that simply doesn't last long... but that's a relative term because if it last 75K miles... then that's still pretty good but is a gamble with smaller cats, especially with not much room for the emission test.
If you got perfect engine with no vacuum leak or any sort of problems.. small cats will do the job. The reason OE put a bigger one in... to compensate for the imperfect engine. It got the extra 'burning' power to pass the emission.
So by now, you got an idea that the cat need to be a good size... so just look at the picture of the cats and you will know which one will give you more confidence that it will give you that extra headroom for emission imperfection.