There is a hymn to St. Pius X by Catherine Maguire/Achille Bragers, “A humble priest on Peter’s throne,” in Marier’s Pius X Hymnal (1953) which makes heavy use of his motto. It is on p. 34 in the congregation edition and p. 141 in the choir edition both of which are available online at http://www.ccwatershed.org/blog/2013/dec/13/pius-x-hymnal-1953-theodore-marier/
There's also a beautiful hymn in the new Traditional Roman Hymnal from Angelus Press, which would fit the bill perfectly: "In days when faith scarce cast a light/In our world's dark decline/ St Pius, you put lies to flight/ that truth once more might shine./ Then pray our eyes once more may see, /From darkness by that truth set free:" and refrain, "O Holy Pius, aid the fight/ to restore all things in Christ." The tune is minor, and stately and bold enough to make a great processional with the right tempo. It's #243 in the TRH for those that have it (the second edition; the first didn't have it.)
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