If it's an Xbox it will be an S. Makes no difference to him, he plays and streams in 1080.
Amazon US have 2 in stock with a bundle: https://www.amazon.com/Xbox-One-1TB-Console-Fallout-Bundle/dp/B07GQ8M9M5/ref=sr_1_2?dchild=1&keywords=xbox+x&qid=1626094222&sr=8-2
(bleh, rushing through lunch).
But there's no point in him getting an X. He plays and streams in 1080. May as well get an S. But if he's getting it for Fligth Sim he's in for a hell of a shock. If people don't turn up to Dangwhateverthatweebshitiscalled or MLB because they're boring... we need some suicide alerts going out. You spend literally hours in the air doing nothing. Literally nothing. it's not a game, it's a simulator. He's going to be staring at a static chat window complaining no one is talking about the game (which isn't a game).
I'm getting on the green screen bandwagon. He already has one so it's no cost. Maybe a new laptop was donated to him? An Xbox seems too obvious a scam.