Marshmallows - you have to buy a bag with both strawberry and regular marshmallows.
Hershey's chocolate bars - I bought 'milky bars' actually they were white chocolate but I've since found something similar to our thin chocolate bars.
Graham Crackers - 'Digestives' are a good sub
They roast marshmallows here but they don't do 'S'mores'. Oliver thought they were 'gorgeous'. He also loved sausage gravy for dinner - could be a budding southerner in our midst!