I know this sounds more than a little picky but I would replace both sides.
Whoever built the side pipes made multiple mistakes most of which have already been tagged by others in the thread. The whoops that visually offends me is the fact the fabricator did not use mandrel bends at the 90˚ point as the headers exit the fender. The result is squashed, ovulated piping.
The bending workmanship makes it look like the work was done by a 1950's muffler shop. The rest of your car looks too good to diminish it with this type of exhaust fabrication quality. The fix as others have already commented is not inexpensive. If you are stepping up for a complete replacement you ought to take the time to look at some of the stainless alternatives available out there. They are quite impressive in appearance and never rust. At the same time get a good set of large I.D. mufflers so you are not choking off the engine.
If you are handy with Cobra type upgrades you might want to buy the 90˚ bend pipes from places like Specialty Products Design (Click here=>
spdexhaust.com). They also have CNC cut exhaust flanges, straight tubing and a variety of bend angles to help you complete the job. You can fab up your own headers and get them welded at a local welder with TIG capability. The finished pieces will be impressive and save you a fairly significant amount of money.
If you are shy about the fabbing process ICE Engine Works sells header fabrication kits that are in plastic. When you are done you cut your stainless pipes to match the plastic set up pieces and get them welded up. Click here =>
ICE Engine Works
Parting thought, the distance from the body you place the pipes tends to some extent be a balancing act between snakebite issues and cooking the paint on the car over time. Too close and the paint suffers, too far and the passengers who choose to forget your exit practices advice get bit — somewhat challenging dilemma but comes with the territory. I would fall down on the protecting the paint side of the argument.
Ed