FOREX is not dealing with RUB at the moment because of the war in Ukraine.
In Oman, the currency used is called Omani Rial, and has the currency code OMR. One rial is divided into 1000 baiza.
Tip! Convert to Omani Rial to the extent that the currency is available, and then top up with American dollars (USD).
Delivery to nearest post agent
Save the receipt and change back for free
Buy currency in advance, no need to search for ATMs