Shipping overseas will cost bucks but if the guy is willing then go for it. It might be a good idea to get the estimated shipping cost and then bounce it off this guy to see if he's ok with it. Just be crystal clear with the person that he pays full shipping. Also make him aware of the time to receive the shipment. If it goes by boat it will take weeks to get there. Also customs could hold it up. Get a tracking number.
With regards to opening the auction up I would not worry about it. The only issue you could have is some person from Nigeria or some other foreign country mess with your auction. I've had this happen on a few occasions especially when selling electronics. Nigeria for some reason is the home of many eBay scammers.