2005 XC90 Interior heater sensor unit

[roncop]

Hi Guys:
My 05 XC90 T6 has the standard heating controls. I decided to remove the dust from the interior sensor (situated in the 3 little slotted vent intake just above the temperature controls)..but alas..with my dainty fingers...I pulled the ball of dust and broke the little ball sensor.
Since then, I have no control of the temperature. In cold weather, its either full heat (where we melt) or 2 degrees lower and we freeze!!!!
I have changed the sensor unit with one I got from the scrap yard and it was defective...(at a cost of $150.00), so I tried dealer...they said the unit is $1350. plus tax, plus programing...?????
Has any one ever had this issue? Do I have to purchase a complete unit, or is a sensor available somewhere that I can replace only the sensor???
Thanks,
Roncop