That exhaust is definitely a stock system. Whether that is a good thing, or a bad thing is depending on personal prefetences. Even with that stubby looking muffler, the stock exhaust is HEAVY....You got lucky there $ 2500 is at least $ 1000 maybe $ 1500 to much money for a 40 year old single not stock
I don't believe the exhaust is
and that is for a low mileage machine
I actually have one like that, except for silver metallic paint. Mostly in boxes though, waiting for time and energy..It came with a hi comp/ big bore Wiseco installed, and a nice pair of Mikuni TM/ RS 34 pumper flatslides. And several exhaust options, with Supertrapp mufflers.