Asda sell a unicorn biscuit-making kit, some unicorn foam sweets. I've seen a unicorn Little Miss book for just a few pounds in Smiths www.whsmith.co.uk/products/little-miss-stubborn-and-the-unicorn-mr-men--little-miss-magic/9781405237918 and I'm sure it would be easy to find a unicorn colouring book and stickers. Smiths also does unicorn stationary such as notepads, crayons and fluffy pens. Claire's has a large unicorn section with hair bobbles and hair clips. I've even seen a unicorn shaped bath bomb in Claire's.