Yes, salt is rampant all over that area. SOME PA vehicles are quite rusty. Perhaps the one you are looking at was Ziebarted when it was new, and will never rust. Get it checked out by a pro, for both rust and mechanical issues.
There are SEVERAL big dealer only car auctions in PA. That’s where Manheim’s headquarters are. Manheim & Co owns auctions all over the country. Their PA auctions are almost as likely to be selling cars from PA as they are from NJ or NY. I have seen hundreds of PA cars transported at least as far west as KS, and resold at other dealer auctios at a profit. The theory being that eastern car owners consider their cars to be dying at 100K, while westerners figure 100K is just well broken in.