We use MakerDAO oracles. The modules Feed and Relayer. The Feed asks for the price and the Relayer delivers this price to the contract.
Feed takes the median from prices from different sources (direct ETH/RUB pair or calculate the price of ETH/USD median (USD/RUB).
Sources for ETH/RUB: binance; cryptocompare; exmo
Sources for ETH / USD: bitstamp; coinbase; gemini
Sources for USD/RUB: exchangeratesapi; cbr; ratesapi