Andrei, the famous map seller from Klimentovsky pereulok. That’s between Metro Novokuznetskaya and Tretyakovskaya. A small stall with the most thoughtful collection of local maps. There since the 90s.
A specialized map store at ulitsa Pokrovka 11, Metro Kurskaya or Maroseyka, tel.. +7 495 749 3200.
An unconfirmed report of a specialized map store at Ulitsa Bolshaya Semenovskaya 10, Metro Electrozavodskaya, tel. +7 495 746 3856.
There was map store at Kuznetsky Most but I’m afraid it is there no longer, replaced by some nondescript boutique.