Is there a larger capacity oil filter that I can swap for the standard #16?

sorry,but no.

I wouldn't even bother. Factory filter on that is more than enough capacity and as you are seeing, the longevity is there. By the mileage you are at, any extra mileage to be gained by filtering it would be minimal and offset by the increased demands on the oil pump, etc. Honestly, no, you can't swap that filter in, also because of the different threads that Chrysler introduced in the 1992 model year cherokee.

The -16 filter IS SAE. The -8 will screw on. It may hit the starter and require disconnecting the battery to change. Just to check; If your oil filter is vertical/upside down you have metric threads. If it is horizontal you have the SAE threads and can use the -8 or -16 filters. If it is vertical, the dealer can supply an horizontal adapter to replace the vertical one. This will give you SAE threads and allow the -8 filters. Don't you love people giving you an opinion you didn't ask for? Just answer the question, just the facts, ma'm, just he facts.