I *strongly* doubt you're going to find an isolated headphone jack with a gold finish – gold headphone jacks are rare enough as it is. As a fan of the glossy black & gold look, I've been on the hunt for a few years now.
The Planet Waves that I linked to is probably your best bet; Warmoth Guitar Parts also sells a ‘deep panel stereo’ headphone jack with a gold finish that looks round from the front, but I’ve had bad experiences with it (two arrived to me DOA). I really wouldn't recommend holding out for a round fastening nut - most will come with round washers anyway so they will still look the part.
I’ll tell you what I did to mount the jacks to the front panel – hopefully you’ll find some of it helpful. My front panel was ¼” aluminum plate; I couldn’t go much thinner and still have thick enough metal for good tapped blind holes. I machined a rectangular pocket in the middle of the panel that was about 0.1” deep, and then sheared a piece of stiff plastic that was slightly smaller than the pocket (so it would fit). I then clamped the plastic subplate to the rear of the panel (in the pocket) and drilled 4 guide holes that barely penetrated the metal panel. Then, I used a drill press on the metal alone to turn the guide holes into 0.125” deep blind holes (very close to the outer wall) and tapped them for 4 -40. After drilling the guide holes on the plastic subplate for 4-40 clearance, I fastened the subplate to the panel with 4-40 bolts to ensure that it was secure. Next, I turned the panel around (front side facing the drill), marked the centers of where the headphone jacks would be mounted, and drilled a small through hole (going through both the metal and plastic subplate) so that the holes would be concentric. Next, I unfastened the plastic piece and enlarged the two holes on it to 3/8” to mount the headphone jacks. Then I enlarged the holes on the panel to 5/8”. To finish, I secured the headphone jacks to the plastic subplate, secured the subplate the main panel, and made sure that the jack was not shorted to the panel.
As you see, you can make a lot of work for yourself if you’re dead set on a certain look.