I would probably do a gift certificate for $100 for friends and $150 for family. Maybe break it down in a couple of vouchers for different stores.

Another option is to contact a shopping centre near them and see if they do a voucher for the centre. Many of the shops in the centre will take the voucher (often except the larger stores like Coles, Kmart, Target or Big W though) so they are not limited to just one store.