Pegging down weed control fabric

Does anyone know where I can get some of the long serrated plastic pegs to use with a very heavy duty weed suppressing membrane? I've looked at the local garden centre, but they were about a fiver for 10 pegs

My garden is now cleared and I've got some of the fabric to put down (hopefully) kill off the brambles and giant thistles. I'd rather not use bricks to weigh it down, as I might put some mulch over the top, and want it to be a trip-free area!

Thanks

I brought some plastic pegs like that to pin down the cloches I put over my lettuce seedings last spring. I got mine in Wilkos - I can't remember exactly how much they were, but it was something in the region of five for a pound! They held down the cloches just fine, even during some pretty bad weather.