What is the ruling on ordering from websites that display indecent images and encourage immorality, and is this considered an encouragement of them?

If it is possible to purchase from alternative websites free from impermissible elements, then do so. If no alternatives exist, then purchasing from this website is not forbidden, while averting one's gaze from impermissible images as much as possible. This is because such impermissible elements have become widespread, making it difficult to avoid them, and "when a matter becomes constricted, it expands." These impermissible elements are not the primary intention of the visitor. What is overlooked in a تابع (subordinate/incidental) is not overlooked in a متبوع (primary/main), and purchasing permissible items from the website is not considered aiding in what is forbidden.