I have been experimenting with my own campaign which has ended up including Fraz-Urb'luu as a central antagonist. My intention is that the group does not have to fight/kill him, however in order to be prepared I have looked around for a stat block for him just in case. Unfortunately I have been unable to find any indication of any supplements or rulebooks with a 5th edition compatible stat block for him.
Presumably, if such a stat block exists, it would be an infringement to post it here, but if I know what I need to buy I am happy to make the purchase. Do any of the Rage of Demons/Out of the Abyss supplements include a stat block for him?