Yep it and XXX are the last 2 35mm movie films made by Kodak. I have not seen short ends in ages but a new 400 foot roll is still around $120-150 you just have to search for it. It is listed as Eastman 5222, Double X and even xx. Sometimes adding Kodak to the search will bring up more.
This is where I got my last roll I see the price has gone up a little but when you figure the price of 4 100' rolls it is still a deal.
http://www.tapesuperstore.com/koblandwhned.html