The 03-06 TJ Rubicons and 04-06 LJ Rubicons came with 16x8 Moab Rims.. That would be it for 16x8's.. Some Late year Limited or Classic XJ's came with 16's as a option I believe but they I am 99.9999% positive were 16x7's
Nothing used that I know of.. The cheapest aftermarket you will probably find is Cragar soft 8's