Ham, cheese, sandwiches, samosas, chicken drumsticks, pizza, crudités, dips, bread rolls (crusty ones), quiche, pork pies cut into quarters, mini sausages (ones cooked yourself and allowed to go cold are nicer than cocktail ones from supermarket), boiled eggs, potato salad, crackers, doritoes, bread sticks, pickled onions sausage rolls.
Brownies, little jellies (bit of a faff, can get little pots from eBay), fruit platter, Although to be honest, at £3 I would consider buying half a dozen of these I am sure after all that food, and a couple of pints they will be fine, and at that price you really couldn't make them cheaper.