I made a quick easy replacement window for one of my Victrola speed indicators of which the original had gotten too yellowed to see through. I used a bit of plastic cut from a produce container and trimmed it with a small scissors, holding the original against it as a template. It took about a minute to do!
I used a Campari Tomato pack. You may use a container from your favorite produce!
The original piece will be tucked away in a marked envelope in the machine for future owners.
Bob