AndyMark and Kauai Labs are both currently out of stock of the navX MXP Robotics Navigation Sensor (am-3060a) and we are looking to acquire one fairly quickly (week 2 is our first event). If a team has a new one sitting around that they are not planning to use this year, we would love to have a chance to buy it off of them.
If no navX-MXP is available, another option you might consider is to use a navX-Micro. You can communicate with this device using the same LabVIEW/C++/Java/Python/C# libraries as the navX-MXP. The navX-Micro is the smaller version of the navX-MXP. The navX-Micro has USB and I2C interfaces, so because of the USB issues which have been discovered w/the 2016 RoboRIO firmware, you could use the I2C interface.
Unlike the navX-MXP, the navX-Micro doesn’t have the MXP Expansion IO feature, and it doesn’t mount directly on top of the RoboRIO - but a 3d-printable enclosure is available. The navX-Micro also doesn’t have the SPI and TTL UART interfaces provided by the navX-MXP - but the I2C interface should work fine for your needs.
If that sounds like an option for you, they can be purchased at the KauaiLabs online store.