My assumption would be that this would require replacing the whole optical block (read: not cheap.)
I'm sure someone with more knowledge than I will chime in soon...
Depending on how handy you fancy yourself, you might be able to purchase a dichroric filter to replace the one that is failing. But you'd have to be able to remove/re-mount the new one correctly.
JVC X750R, 133" DaLite HP (2.8 gain), OPPO UDP 203
Denon X4300H, DIYSoundGroup Fusion 15 L/C/R, Mirage FS V2 Surround, Mirage Omnisat V1 Surround/Atmos