Beach kit - beach towel, hat, thongs, sunscreen (if you're really broke shop at k-mart or just buy one of the items)
Magazines - grab a couple of his favourites (cars, fishing, camping, four-wheel driving, men's health or sport)
Character t-shirt - Big W, K-Mart and Target have plenty of Star Wars and Superhero gear
Hamper of some of his favourite foods
New BBQ tools
Steak knives
Movie tickets
Board game
Car cleaning kit with a voucher to clean his car