Is this not the case with the Brazilians? Mine is stamped with both "S&W D.A. 45" on the left side and "Smith & Wesson" on the right side.
Judging by your pics in post #15 you have a commercial style Brazilian M1917, and I would expect that your example's barrel is not a leftover barrel from the original WWI U.S. M1917 contract run, but a newly manufactured barrel for the later commercial and Brazilian "commercial" style guns.
Later post WWII delivered Brazilian examples assembled using "found" U.S. M1917 contract parts most likely
will not have the "SMITH&WESSON" marking on the right side of the barrel if built using the "found" original U.S. M1917 contract barrels...….as original U.S. M1917 revolver examples do not have the marking.
My Brazilian M1917/1937 example, delivered in 1938 was assembled using commercial model M1917 parts. (Not original U.S. contract M1917 parts from the WWI era.) It
does have the "SMITH&WESSON" stamping on the right side of the barrel, same as yours...….and same as my slightly prior 1930's era true commercial model does.
As a sidenote, the correct grips for your example most likely would be the commercial checkered grips with silver medallions similar to the bottom revolver in the pics provided......which is a "commercial" Brazilian M1917/1937 example delivered in 1938/prior to WWII.
While hard to actually see in my crappy pics, the "SMITH&WESSON" marking is absent on the true U.S. contract M1917 example but present on the commercial style Brazilian m1917/1937. Maybe if you zoom in enough you can see the faint "SMITH&WESSON" marking on the Brazilian's barrel. Maybe....
I'll try to get better pics tomorrow.
HTH,
Dale