Just the lens, or the camera as well?
Is a heater on the lens out of the question?
Are you looking for a C/CS mount lens? M-mount?
Whats the temperature range? Is the lens going to go from +30 to -100C?
1/4" sensor? 1/2"? I'm guessing you're looking for something in the 3mm range?
I have no ides off the top of my head, but if you can provide a few more details I can look through some of the catalogs I have from lens companies and see if there is anything even close as a lead.
I don't think I've seen a lens go below -60C.
For -100C, that sounds like something you'd need specially made/ordered. You should also take into account how fast the temperature is dropping. I'd imagine something going from room temperature to extremely low temps too fast is probably going to destroy most lenses regardless of their described resistances.