iPadOS 6.1.3 (build 10B329) is an official Apple over-the-air update for the iPad 2 (CDMA). The update package is 68.2 MB. This is a delta (partial) update that requires 6.0.1 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: 8fabbc78eb60af77c296eee2022141fa7105997c.zip.