It's the same set as an 810, so you can use that Sams.....which is 53-12. I've rebuilt a half dozen of them.
Honestly you really don't need a schematic to rebuild them, they're easy enough. A little tip: there's a sand resistor mounted just under the picture tube that's I think 750 ohms. Replace it with a 10 watt wirewound as a part of the restoration process....they tend to be old and crumbling and cause focus issues.
One of my favorite chassis of the postwar era
