I have an IR thermometer... I have some time and can do tests. Exactly where do you want readings from?
Yes, testing this stuff with an infrared thermometer would be fine. For doing this, I would try like this:
Recording a video-file for to heat the camera
Testing the cam at some different temperatures (low, medium, high for example)
Measuring at each temperature some parts inside the camera. Sensor bottom side, sensor top side, other parts
shooting a pic at each temperature and extract the temperature, shown in the exif of the pic.
Writing down the according temperatures here in this thread: exif-temp, Celsius by ML, raw by ML, IR-temperatures.
Beeing very quick in testing this.
I think, someone started measuring with an thermometer some time ago, but nobody followed him. It would be interesting to see, wheter the measured temperatures match to temperatures, showed by ML or extracted from exif. But I think, this test isn´t very simple to do accurate, because, if the lens is removed, the temperature inside the camera will change very quickly.