I'm not sure there's a manuscript source for that Kyrie. There's no century indication in the Solesmes editions, and I don't see an entry for it in Olivier's Guillou's listing of the sources of the Vatican Kyriale. Compare the Medicaean edition:
https://vmirror.imslp.org/files/imglnks/usimg/0/08/IMSLP291258-PMLP472804-editio_medicea_volume2.pdf#page=32