"What is the replacement cost of the oranges they had in inventory?" That is not relevant, the fact is they raised the price to the new price knowing all along they would make a windfall profit on their current stock which they paid less for.
It IS relevant. Market price is NOT dependant on costs of inventory. If they were to sell at below market price, then they would forego profits. You, as a consumer, might consider that nice of them, but they are not in business for the purpose of your viewing them as nice.
Do you view their "windfall profit" as something immoral or unethical? If so, then you are buying into the leftist idea of economic fairness that leads people to vote for democrats and other Marxists.