Paris Stamp Dealers

I will be in Paris in early November and I'm interested in recommendations of retail dealers to visit. I am familiar with the outdoor Le Marché aux Timbres du Carré Marigny off the Champs Élysées, and do not need info on that. My research indicates a number of shops in rue Drouot in the 9th Arr., and several appear to have current online information. Does anyone here favor a particular dealer in rue Drouot? My interest is classic era singles and sets, not covers, supplies or catalogs.

One of my favourite places to look for stamps , covers and postcards is the "passage des Panoramas" very close to rue Drouot. Many shops there.

Not visited, but there is a dealer in the Palais Royal, open Monday-Friday, amid the fashion outlets. The real attraction is the Palais Royal itself - walk in the footsteps of Colette!