I found the same scam, with selling a car and trying to buy a camper.
Selling a Hyundai Elantra, guy wanted to buy it for his Dad, in New Zealand, he was in New York and the shipping agent was in the UK... Um, no thanks.
Spotted an add for a 2010 Jayco Swan in a printer caravan trader mag, rang the number, left a VM. Next day, I get an SMS advising how to proceed. The camper was located somewhere between Darwin and the QLD boarder, so very hard to get to. Ended up finding an old add from Gumtree, where they stole the photos form, was actually in Vic..
Always, always, always, proceed with caution. If you cannot see it, put your hands on it, run like buggery...