There is no quick fix
Assuming that is a vast conspiracy of international oil companies, it doesn't matter because none of them are based in the US or under any sort of US authority. they are state owned foreign companies, so they dont have to lobby america for shit. China National Petrolium Corporation does not give a hoot what the US thinks, and the US can't tell it to do anything. All US oil companies make up less than 10% of the market, so there's no US policy that can work.
If you want to put a price control on oil, someone still has to buy it, and again, they're buying it from people who will set a price, whether it is fair or not, without regards to what the US wants. You can force Shell to sell gas for 2.50 a gallon, but if the price of a barrell of crude oil is 150 dollars, Shell is going to go under very fast. The only solution then is to have the gov't buy it directly at a loss, in which case, the people are still paying for it in taxes, and nothing has really changed except whho you write the check to.
Back to this 7 sisters business, I don't buy it that there is some global conspiracy to set the price on oil mainly because the 7 international companies are from countries that do not like one another, and they are state owned so it's not a matter of greedy businessmen. Saudi Arabia and China do not get along, and Saudi Arabia and Iran are at odds all the time (Iran's threat to mess with the Strait of Hormuts would be a serious blow to the Saudi economy).
However, you can't dispute the fact that they're big companies, and again, they became big because they are all either 1) independent oil producing countries (Brazil, Iran, Venezuela, Russia, Arabia) or 2) they have huge demand increases (Brazil, Russia, China, Malaysia). Compute that in with the fact that India and China are growing at a double diigit rate, and have been for the last 20 years, and you have literally half of the world population competing for the same amount of reserves.
Supply and Demand