OK it's too late for this years' presents .. but don't forget, Christmas will be here again very soon, in roughly 363 days.
10m rolls of good quality wrapping paper at 25p / roll seems cheap enough.
So 40m for £1.
I don’t know whether this is a national offer, but I suppose a quick call to your local store would be easy enough to do.
Some other shops have 6 (3m rolls) for a pound, which is more than double this price.