Although various web sites claim you can use larger filters, it isn't advisable. The correct XJ filter has an anti-drainback valve to keep oil in the filter when the engine isn't running. Many (if not most or all) of the suggested substitutes don't have this valve, allowing oil to drain out of the filter and resulting in "dry starts."
So many people have gone 250,000 to 300,000+ miles using the correct filter that I simply cannot see the appeal of risking the engine to a non-recommended filter.
JMHO