These are a fiver in Asda! Was going to buy a load of them and chuck them on eBay, but only one left in my local B&M (Blackwood, S Wales). Not sure if it's nationwide, but worth checking.
A kit containing: Bamboo Rolling Mat, Sushi Nori, Sushi Rice, Sushi Su Rice Vinegar, Japanese Soy Sauce, Wasabi Paste, Sushi Ginger, Chopsticks
Just add prawns, smoked salmon or crab sticks to make sushi Maki!