Thanks for all your help and advice. I ordered the lens from Fastlane for $16 (includes overnight shipping). I need to replace the lens before the inside gets too dirty. It is raining here and there is no lens left to keep the moister and dirt out.

Since I am going to be under the car, I am thinking of a thorough inspection of the harmonic balancer as well. Is the part number visible from under belly of the car?