3/8" HEX DRIVE socket ID HELP?!?!?

[zoomieport]

I picked these up today, anyone have a guess on the maker? The only markings I find are the sizes (15/16, 7/8, 11/16, 5/8, 1/2)... They appear to be vintage and of nice quality.
Any help is appreciated!!!
Mike

 

[55Savoy]

Duro Chrome or Industro made a lot like that