Just put a small (3% portfolio weight) into KazMunaiGas (Exploration and Production).
This is an unconsolidated subsidiary of the Kazakhstan National Gas company. This subsidiary is quite a large company – worth c$4Bn. The value of the cash / current assets is about $10.1 per share (more if you exclude treasury shares) whilst the share price is about $10. In effect, you can buy an oil company pretty much for free.