[Arran]

 I would guess that what you mean regarding a thorough and a beautiful restoration job was in reference to the electrical side of things and not the cabinet. With regards to the cabinet, quite frankly it reminds me of a typical "Antique Mall" style refinishing job, no grain filler, no tone spray/shading lacquer, satin finish, it may look acceptable but it certainly was not how they left the factory. Sparton sets of that era were no different from any other manufacturers or the time, the cabinets had had shading on the solid wood portions, and a gloss lacquer finish, like a piano.
As for the little dial window, that certainly seems like something Sparton would do, Sparton was never completely sold on the idea of automatic tuning mechanisms, even on their large models they tended to keep the number of pushbuttons to a minimum, I doubt whether they ever built a set with a motor driven dial. I have a high end Sparton model from 1941, it has ten tubes, but for whatever reason they only added a pushbutton bank of six pushbuttons which is something that a lower end Philco model would have had, even on the Canadian market.
Regards
Arran