This is a great deal on this excellent all-in-one printer. M&S is the last place you would think of looking and it isn't even listed on their website. You can only get to it via the direct link given here or by searching for product code T041009 on the M&S homepage.
I telephoned today (September 2nd) and they do still have stock. It comes in a M&S branded box with a sticker price of £199! Canon are bringing out a replacement soon, so when it's gone, it's gone.
Go through Quidco for an extra 3% cashback as well.