This is a recent postcard picturing one of two 1958 Soviet miniature sheets issued to commemorate the Centenary of the Russian postage stamp. История почты is Postal history. Here the two sheets are shown together:
Here are some larger images of the two 10 kopeks stamps (Source: http://commons.wikimedia.org/wiki/Category:Stamps_of_the_Soviet_Union,_1958). The first one is a Prince's scribe (15th century); the second is a messenger (16th century).
I found a nice Russian Postal Shop in English (http://postal-shop.ru/en/) that has many postcards available for sale, including the one I have. The minimum order is 20 euros. The site seems to be oriented toward Postcrossing members--it has a page About Postcrossing,
This is a post for Sunday Stamps at Viridian's Postcard Blog