Not factory original, that's aftermarket gold fill... Brownells currently sells a product called Lacquer-stik, comes in gold, red, black. etc.
The popular product was Bonanza gold-fill inlay powder.
The gun is just a solid shooter grade gun, nothing special... It's missing the upper side plate screw which lowers the value, and it's unusual in that it looks to have a lanyard swivel on the butt, which was not standard on a 4th Change, and that being non-original can also affect value, but not as much for a shooter.
Concerns about the swivel being added after it left the factory... is how well it was installed, many amateurish jobs in drilling the lanyard hole illegally obfuscated the serial number on the butt frame. On guns from the factory, the s/n is spaced out to allow for the lanyard hole. Yours looks to be drilled forward of the s/n, which is usually an indicator of it being added after it left the factory.
Pricing depends on you location, our prices in CA are crazy high and very atypical, so I'll let someone else comment on selling price.