I've never heard of one, but then I have to admit that I haven't looked too hard.

C.S. Lewis is only out of copyright in certain countries right now; Canada is one of them and Australia, I think.  It'll be another thirteen years in the UK (well, fourteen really--beginning of 2034) because they have life +70 rules.  Also, since the Chronicles are still in print and easily found for reasonable prices, at this point it may not be worth anyone's while to do an edition like that.

Hi Dimitris,

I think by the time the Chronicles started to be published in one-volume editions, the publishers had already decided that the chronological order was the "correct" order, so that's how all the one-volume editions are, as far as I know.

That's interesting that the Chronicles are out of copyright in Australia — I'm Australian (though I now live in Britain) and I didn't know that. I thought our law was "life + 70", which I just checked and it is, but it used to be "life + 50" until 2004 and the new law doesn't apply retroactively to anything published before then, which includes the Narnia books. However, they don't have a separate Australian publisher, so we've always had the British editions. I guess that means an Australian-based publisher COULD legally publish new editions, including a single volume in publication order, but as @aileth says, I don't think most publishers would be interested while the current British editions are still in print and easily available.