Seventeen-year-old Chloe, who had worked part-time at the South Shields agency since January, died with Liam, 19, in the suicide bombing at the Manchester Arena on May 22, which killed 22 people.
Agency director Graeme Brett said that so far the giveaway had received donations from more than 30 travel firms with prizes including city break trips, flights, vouchers and food and drink.
Tickets are priced at £5 and can be bought via bank transfer.
Those wishing to sell tickets can contact sales@westoetravel.co.uk.
The prize draw will be made on August 31.
Meanwhile, a joint funeral for Chloe and Liam will take place on Thursday (June 15).
The public service will be held at St Hilda’s Church in Market Place, South Shields, at 10:30am and will be followed by a private family service.
At the funeral, family flowers only have been requested and anyone who would like to make a donation to Westoe Travel’s fundraising appeal for Chloe and Liam’s families may do so below.
Launched by Manchester-based homeworker Ken Garrity, of Ken Garrity Travel, and Pole Travel director Jill Waite, the campaign has so far raised more than £2,300.
