Do you have access to a second system to steal parts from? I don’t know of anyone stocking parts for this series anymore.
Between the [https://en.wikipedia.org/wiki/Capacitor_plague|rotted caps] and burn’t out [http://www.act1.com/Flyback-Transformer.html|flyback transformer] coil which is the source of the squeal you have quite a few parts to replace. Are you sure you want to make that investment?
You’ll want to find the service manual before opening this system as the CRT stores quite a bit of juice which if you’re not careful can hurt you!