Call a muffler shop for a quote.
gonna go is an open statement, are you having any issues like a loud exhaust?
An exhaust system generally does not come with jets since they don't know what kind of carb you are running. Only way to get a set of jets to match the exhaust is to know what carb you are running, and any other engine mods.
It will just get louder and louder till it drives you crazy - then you will change it- cost will depend on quality you want on your car
