(Reuters) – Russian internet group VK on Monday appointed financial advisers for proposals to be made to holders of its $400 million bonds who seek to demand their redemption rights, just weeks after flagging issues with servicing its debt. The London-listed firm, which also runs email provider mail.ru and has operations in gaming and education technology, saw its shares plummet following a U.S. sanction on its chief executive that dramatically changed VK’s prospects. The company said on Monday it has appointed Aspring Capital and Serdika Financial Services to develop options for holders of it…