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If you want to do the same thing the sensor is ~$250. You can get one on a devboard from sparkfun for $260: https://www.sparkfun.com/products/13233

Adafruit has a low-resolution thermal sensor (8x8 pixel) for $40: https://www.adafruit.com/product/3538

The SparkFun sensor is the Lepton 1 with 1/4 the resolution of the Lepton 3 (80x60 instead of 160x120). He really did get a great deal on the sensor!

A quick google search shots GroupGets [0] has a Lepton 3 sensor, no breakout board for $240.