4 Rear TJ flares can be used...looks pretty good. I like the way it looks more uniform on the XJ. They can be had for a good price if you can find them used...or you can order them new for about $150 US or so...whatever that works out to be in Canadian money.
Here's a picture of 4 rear TJ flares on an XJ. I'm still considering this as an option...right now, I have no flares and like it....my state doesn't really have tire laws, but I'm only running 31" tires with 4.75" backspacing on the wheels, so mine stick out from the truck about an inch at the most.