That thermistor has an unusual resistance at 25C, so it's likely to be hard to find a good match. The closest I found was https://www.digikey.co.uk/product-detail/en/epcos-tdk/B57891M0682J000/495-3071-ND/652254.
Can you adjust the firmware or the hardware that is used with it so as to accommodate a different thermistor?