After the fall of the Soviet Union and the beginning of a new political “era”, lots of things have changed in Moscow.
The city now competes with other European capitals in terms of stores diversity and richness of offers; hence, it is probably best that you devote at least an afternoon to exploring the most famous shopping center in the area: the GUM.
Take your time to see at least a few shops: you'll be surprised to discover that prices are a lot lower than you may have expected. Have fun!