The federal register for diplomas for secondary professional education and higher education in Russia can now be accessed at this site:
http://obrnadzor.gov.ru/ru/activity/main_directions/reestr_of_education/
At the bottom of the page, under Уровень образования, select the type of education for the diploma in question.
See original post for additional information about the database: https://theconnection.ece.org/NewsItem/1405.