Assuming they are currently lsted separately you can end them early via the dropdown menu for each item on your selilng page.
Then just create a listing in the usual way with photographs of each item and the one postage price. So for instance, if it's seven lots of McDonalds toys each containing 6 toys your title would be 42 McDonalds toys.
If you want to use direct postage you can look up Royal Mail prices to zone 3 and add international postage to the listing. Or you can use eBay's global shipping to send to the UK hub for forwarding to the buyer.