https://udayton.edu/imri/mary/o/our-lady-of-victory.php
Finding the original 16th century prayer(s) would be a journey, that is for sure!
I found this note:
Note: On Oct 7, 1571 the Christians won a major naval
battle at Lepanto against Turkish invaders. Pope St. Pius V
had called on all Christendom to a Rosary Crusade in order to
seek Our Lady’s intercession. Once the battle was over, the
victory was miraculously revealed to St Pius V, who remained
in Rome. That year he declared October 7 to be a universal
feast for the Church - Our Lady of Victory. He also inserted
the title “Help of Christians” into the Litany of Loreto as an
act of praise and thanksgiving to her. Two years later, Pope
Gregory XIII changed the feast to Our Lady of the Most Holy
Rosary
Here
https://uploads.weconnect.com/mce/0...e2db037428f1d3/Novena-Our-Lady-of-Victory.pdf