Musescore's online community has lots of transcriptions people have done of these types of charts. They're free to download, and you can get the musescore file (or, I believe, musicxml if you use different notation software) and then chop up parts and switch around instruments to fit your group's needs.
I love Youngblood, and Nat is an absolutely incredible sousaphonist, it must be a joy to play with him! My brass band does a cover of their cover of Killing Me Softly.