YouTube playlist of cajons made in Russia:
Note that not all manufacturers have current YouTube videos. The list on this page includes websites and VK pages which may contain videos not on YouTube. The list on this page is actively maintained, the YouTube playlist is less frequently updated.

Listed above are links to the cajon drum builders in Russia as retrieved by Internet searches in March 2018. I am sure there are many others not listed. Please send me updates and correction if you have additional information. Thanks.