The 29 does not look reblued to me. The normal refinishing marks stamped on the grip frame by the factory are R-Bi, R-S (each inside a rectangle), or a B followed by a diamond. There is usually a date stamped on the frame also (i.e. 9 62 would indicate a refinish in September 1962).
The stamping of an X or other letter on the yoke and grip frame was a common practice and does not indicate a reblue or other type of repair or modification.
Rollmarking of the S&W logo on the side plate of Model 29s in the 50s and 60s was often light and can lead one to conclude the revolver was refinished.
Bill