Many years ago, I bought a few 3" cat converters (for my drag race minivans) from Don's Hot Rod Shop in Arizona. 800-888-8892 At the time, they carried the Products for Power brand and they were very affordable.
Just for kicks, I picked up the phone to call them (I still had the number memorized). I was told that DynoMax bought out Products for Power, yet the cats are still produced and still carry the same part numbers. He said a 2.5" model runs about $85 and they have them in stock.
If I needed a cat, this is what I'd do.
My fleet: 91 Miata, 98 Wrangler Sport
, 01 Suburban 8.1L, 14 Impreza, 80 Grand Prix LJ
Jeep mods: 4" longarm + 1" BL, 35" KM2s, 4.56s with dual ARBs... and lots of scratched armor