Update 3: The Sun Comes Up

 

I now have briefly checked all galleries (chapter film) from Felix. I noticed that Claude Jarman Jr. (who recently died) also wore bibs with a high back I didn't recall. Also some other scene like sleeping in bibs and the other boys dining at a table. I read my post and obviously I still haven't seen the 2nd half. I have now briefly checked it and the bibs/scenes are much better than the bib with low back in the first half.

Previously rating 7, now probably more (8 or 9) but I have to re-check it completely and more carefully. Brand might be Hercules (squared lid) or less likely Boss, Cone, Pioneer/Montgomery Ward, Test, Boss of the Road or Wrangler but  many 40s brands looking like this.

https://biboverallsfilms.blogspot.com/2011/01/sun-comes-up.html