I have a replacement for now.

Hmm..I'm not really sure that plastic bags work like filters do. Filters are supposed to get rid of the glare from your monitor, but plastic bags aren't specially designed to do that. They're specially designed to hold objects, and I'm sure most plastic bag manufacturers would not waste their time adding extra functionality. Also, in personal experience, I've found that plastic bags actually generate worse glare than the monitors themselves, so that kind of defeats the purpose. I used to keep a plastic bag on my monitor to keep the dust off, see? :D