S320 Replacement LENSES?

Hello.  Off and on for the past year or so, I've been looking for a replacement lens for the Dell S320 projector.  Everyone I contact wants to sell me a lamp.  I don't need a lamp, I need a lens . . . now I need two of them, in fact.  I've contacted our institution's Dell representative; dead end.  I contacted Dell part sales directly, and they sold me the lens CAP.  I've searched and searched every way I know how, and I'm coming up empty.  Does anyone here have any suggestions?

One lens went bad on us about a year ago.  We couldn't figure out what happened to it.  I guessed that someone tried to clean it with some sort of abrasive cloth or solvent.  Now, just in the past couple of weeks, another projector was giving us a problem, and this lens is even more damaged than the first one (we have three of these units).

Our best guess at this point is that they're cooking, and melting a little bit.  The coating is worn off in an area about the size of a dime, and the plastic (the lenses are not glass) is rippled enough so that you can both see and feel it.  The inside of the lens cap is also marred in an area about the same size and position as the damage to the lens.  I'm assuming these are gone with no way to repair them.  I think users have not been allowing them to cool properly before unplugging.  We'll do better in the future, but for now I really need to get these lenses replaced.

I sincerely hope that these $560 (or so) projectors are not now useless because of a bit of melted plastic on a part that I would think should be easy (or at least possible) to get.  Help!