Have you tried one of the following sites?

- https://paxful.com/russia/buy-bitcoin I guess you can sell there aswell.
- https://localbitcoins.com/country/RU Peer to peer transactions.
- https://gatecoin.com/ ( Not sure if they're legit, you should research them  a bit more. )
- https://cex.io/ - I believe they support russian banks aswell. )

And if you really want to do it the hard way, you can transfer your BTC to virwox funds, and transfer those to RBL. https://www.virwox.com/