That is a nice shooter grade Model 1905, 4th Change you have there. It could have been carried in WWII, but it also could have been carried as a private purchase in WWI as well.
I would guess that the gun has been re-finished and looks to retain 100%. The reason I suspect a refinish is, first the stocks are very worn, not matching the finish and sccond the S&W logo edges look buffed. A solid job that retains the correct case hardening of the trigger and hammer. Many refinished guns blued or nickeled eveything. I would also say there look to be some soft edges in the flutes of the cylinder and elsewhere, but you paid a fair price for the gun, so go out and shoot it. With a revolver of this age, keep your loads mild. Standard 38 Special ammo should be fine, but I usually reload down to 125 grain bullets and shoot around 650 fps to be on the safe side. After all, it will be 100 years old in a few years.
As late as a couple of years ago, these guns would have sold for under $200, but now it is tough to find one for under $300 in any shape.