My 85 Catalina 30 has the 12 V interior lights that look like they belong on an RV- opaque white plastic. All of the covers have heat damage and are crumbling and need to be replaced. Catalina parts says they don't stock them and can't get them. Has anyone had the same problem and located either the OEM or a source for replacement light covers? They are approximately 5 1/2 inches square and snap on and off the light fixtures. Thanks.