Was thinking of selling my 1968 17-2.

Bought a year ago from seller who IIRC, said cylinder was either 'timed' or replaced by S&W. I only shot 30-40 rounds thru it and shoots perfectly, but I am wondering if the cylinder should be marked or another area on the gun should be marked re: cylinder change? Lock up, timing etc are perfect but cylinder is a hair less "bright blue" than the barrel and frame which have a near-27 bluing.

Box it came to me in was the modern plastic S&W box with a S&W white label on each end referencing the gun's model and serial #.

Gun is in great shape but if i sell it i don't want to misinform potential buyers.

Thanks for any help.