Just to keep things from being confusing....there is no "high output" 4.7L for 2008 and later years. They are all the same, regular 4.7L's.
There are no marketed headers at all for the 08+ 4.7L's. Gibson and OBX were supposedly working on shortys, but nothing came of it. I'd say contact them to show that more people are interested. But realistically, you're looking at having them custom made.