Adiyen has heard that during the 9 days of Navarathri that Durga Devi is worshipped and it is mentioned so in the Shaketya tradition as spoken about by Shivan. Are there any references to Navarathri in the pasurams of Sri Vaishnava tradition, or the Itihasa-s and Purana-s? Have our Purvacharyas celebrated Navarathri?

Navarathri worship is mentioned in Sri Lakshmitantram. As a conclusion of Navarathri, a related Srivaishnava worship was determined and GSPK has conducted a discourse on the greatness of Navarathri. One can listen to this discourse through the link below.

Navarathri is related to the worship of Lakshmidevi. See the PDF through the link below which has a detailed collection of relevant Lakshmidevi strotras, Prabandham-s, forms, and days associated with Lakshmidevi.
https://www.sampradayamanjari.org/sudarsanam-guide-to-upcoming-events/