That being said, Mbappe is not the only available goal scorer in the market. Assuming it was last market window, I will say that there was shortage of good strikers because many of them were I active contracts but this time that the season is ended, some of them will be out of contract but even if they are still under contract, it will be easily negotiable.
Real Madrid should look the way of Victor Osimhen or Harry Kane for a long term replacement of Benzema.
Real Madrid will certainly want to get Osimhen in the team, and undoubtedly Mbape would be very interesting to them too, but PSG will definitely not let him go, especially since they have already lost Messi. But Napoli may not be able to keep on to Osimhen, because the player is very promising, and Napoli is not a financially strong enough team to keep him.