As for the space, this bag has a volume of 18 litres. It only comes in one colour, red, but it does look quite neat.
From Amazon
Fjallraven 23524-326 Kånken Laptop 15" Sports backpack Unisex Ox Red Size One Size
The product is available from £89.76 at international stores.
Hardloop
Fjällräven Kånken Laptop - Travel backpack Ox Red 15"