Golborne Vintage Radio

I recent bought an excellent fully operational Hitachi V209 'scope with one minor issue, it appears that someone in the past has tried to clean the plastic blue screen protector with some sort of solvent which has caused it to bubble. In operation and when lit by the 'scope CRT, it just looks like its covered in rainwater drops which is very annoying. I have looked everywhere for a 1mm blue sheet but cannot find one (they all seem to be 3mm!). It's got to be around 1mm in thickness otherwise it will not fit into the outer frame cover.

Can anyone offer any advice or guidance here please?

Best Regards

Just a quick update, I managed to replace the dripping looking blue plastic screen protector with some material cut from a blue acetate gel light filter sheet. Its not as thick but certainly does the job and I have extra material just in case it needs to be replaced again (I do hope I wont have to!).