'90 Chevy Sub. exhaust question

[OSUCowboy27]

Well, the tailpipe rusted off right behind muffler so I had to wire up the muffler and take off the tailpipe. My ? is should I replace the whole system including the cat or just replace the tailpipe after the muffler. I have 109000 miles on this vehicle and am leaning to replacing the cat and then just straight piping it the rest of the way. Any thoughts?

[taillight]

If the cat. is working , keep it and replace the rest.