FYI the group, most cities have a plastics supply house, listed under Plastic in the directory yellow pages, that can supply small quantity pieces such as new inserts for the lights. The stuff is pretty easy to work with too, so with a very small effort it is easy to fabricate new light covers, etc. If you are mechanically challenged, most of the places have fabrication capability too, so could make anything you need. Just give them the old part and see what they can do.

Doug