Store in Paris that sells Cuprinox on a Sunday? [Moved from Cookware Board]
Not much shopping in Paris on a SUnday but if you are staying overnight at least, and know what piece you want to buy you may well be able to purchase by phone or internet and have it delivered and waiting at your hotel when you arrive. I did that once - can't really say how many places will offer that but worth an e mail if you have time before your trip.
Just a couple of thoughts. The concierge or manager at your hotel may have a suggestion. It's not likely that any store, anywhere, will have the inventory of Cuprinox that Dehillerin has. If you know which piece you'd like, you can go to www.e-dehillerin.fr and Email them and ask if they can help you.
6 years ago, I bought the 5 liter Cuprinox saute pan (without lid) from the Mauviel factory in Normandy by mail, but the mail-order service was discontinued.
Currently, Dehillerin is selling that pan for 156.60 Euros, or roughly $220 US (VAT is not included). Sur La Table, by comparison, sells it for $590 US (that includes a copper lid). Even with a gratuity for the concierge, and maybe a delivery charge to your hotel, the saving is monumental, and, as you surely know, Cuprinox pieces are something to treasure.
There's a way to do this, if you try. Also, Dehillerin will ship to your home, but I looked into that. The shipping fees, for some reason, are very burdensome, and consume most or all of the saving. Best of luck, you'll love the Cuprinox.