i've got a black on black 2005 XJ8L loaded with 89,000 miles. I'm getting error codes 430 and 111. They started a couple months ago, but then they went off by themselves. Now they're back on. Anyone got experience with these two and where you go from here? Do NOT want to put down over $3K for new cat's. Assuming it's the Cat's and not sensors, are there after markets that work for this car in California? do the 2 different codes suggest it's something else?

ME: this is my 5th Jaguar beginning with a 1988 VP when they first came out. I've never owned one past the warranty period and am not into self repairing....just need to find a way to reasonably fix this little issue