rusefi.com

Had that idea for an infrared tire temperature sensor, even got myself an MLX90621ESF-BAB-000-TU 16x4 sensor two years ago - well, apparantly this was already done by http://www.izzeracing.com/products/infrared-temperature-sensors.html

$175 for a naked assembled PCB edition, $300 in a case (wow, that's a $100 case), and $1750 for a set of four sensors w ith wiring.

That actually looks like a pretty cool (no pun intended) setup.

Looks like that case is USA machined, out of billet aluminium then PCB assembled, and fully potted. I can see how that costs $125. However for an extra 1oz in chassis weight, I can also see how you could mount it inside a standard square enclosure, and then pot it yourself.

If you need to do a lot of PCB box it's cheap ...
HAAS milling CNC ...
Start 4:00
https://youtu.be/2fuYj4trEGg