Are you referring to a TV or a radio?
For radios I went to Universal Schematic Locator.
I came up with several:
Montgomery Wards
BEITMANS VOL 12 (1952) PAGE 78-79
25WG1570B, .
25WG-1570B.
25WG1570C.
25WG-1570C.
25WG1571B
25WG-1571B
25WG1572B
25WG-1572B
RIDERS VOL 16 PAGE1
PURE OIL CORP.
5D25WG5025
Sams (i think they may be tvs)
Quasar a19t25wg-set612-folder2
Quasar a19t25wga-set627-folder3
Quasar a19t25wgl -set627-folder3
Wards over 30 serial numbers (too tired to type them all) they all have 25wg27xxx
There are other sources
Which aren't used as much or as popular.
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Page showing consolidated schematics and servicing
Factory service publications)
And like what you stated other brand names
Some other companies may even have the same chassis number .
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I'm a Science Thinker, Radio Tinkerer, and all around good guy. Just ask Me!