They can be found for reasonable prices. I picked mine up for under $22K. Some out there are in the $18K area. '03 and '04 are most desireable because '02 and earlier had problems spitting spark plugs because the heads weren't threaded deep enough. The problem affected 1 in 4 Lightnings I believe, but it was a warranty fix, so it's probaly even more rare now.
Check out the
www.nloc.net for sale section, that's where I found mine.