Is it permissible to sell copies of the Holy Quran that are distributed for free by an Islamic embassy, and to use the proceeds to cover the mosque's needs and expenses?

If the distributed Qur'ans are an endowment (waqf) for the mosque, intended for reading, then it is not permissible to sell them, due to the necessity of adhering to the condition of the endower. However, if they were provided as assistance to the commercial library affiliated with the mosque, and their distributors did not stipulate any condition, then there is no harm in selling them to the public.