I know it these were cheaper at Go Outdoors, but there are more ASDA's around and the Go Oudoors deal has finished.... I think?
Anyway, you can also have it sent to your store for free, or just pick up instore if in stock. My asda has plenty.
I know ASDA has 25% off all camping stuff... but this is the only real "bargain" I saw in my local store, even with the 25% off the other overpriced stuff.