Thanks for the info and the suggestions!
A quick Google search gave some interesting results and a couple of options to investigate. It may be possible to find the original covering material - the ad showed what I believe was a Raymarine
display unit - if I can find a commercial friend to order it for me, or also found Staples, etc., may sell PC notebook and other device "paste on" filters that may work.....
I'll do more investigation and post and update to report what I find.