I'm afraid it's the beginning of the end..... but...
If the displays on the KLN89B was half as good as the rest of the unit, they'd last forever. Unfortunately, that's not the case. And the company that was making replacement displays is no longer, and the last I heard, didn't have any more stock to sell.
The good news is that used KLN89Bs are selling real cheap right now. Just buy another one with a good display, slide yours out and slide in the new one.