I think I understand the situation.
Russia produces roughly 10% of the worlds oil supplies and consumes roughly 3.7% of the world oil supplies, this means that worst case 6.3% of the world oil supplies will go amiss in the case of a total boycott.
However - I am sure that some of the neighbouring Russian lackies and international pariahs are more than happy to buy some of the boycotted Russian oil. I am thinking about countries like North Korea, China, Myanmar, and probably Pakistan and India. While Iran belongs to the same lot, they probably have enough own oil. Russian lackies will make sure to reduce these 6.3% to less than half - maybe use all of it.
This means that any western boycott might mean some reshuffle of oil supply lines and it might mean as well less western money for Russia. It would however in the midterm not materially impact on our oil supply. Sure - there would be some initial jitter until all the oil tankers are rerouted ... and maybe oil prices would lift a bit. What's the big fuss? Oil is ways too cheap as long as people are happy to waste it. Lets give them an incentive to drive more economical cars, to drive less, to teach children to walk instead of been driven and to put their mechanical toys into the storage instead of polluting with them our environment, shall we?