Remington made a slug barrel with adjustable sights that had a rifled screw in choke. Don't know if you could find one. It is a factory barrel that would only need a Turkey choke.
I have one. It came with a Rem. rifled choke from the factory and adjustable rifle sights. I use several turkey chokes in it. My favorite is the Remington .655 Ventilator and old Federal Premium 3 inch 2 oz. 7 1/2 shot.
Been down this road. When Rem made their barrel for chokes they would have the business end bulged slightly to accept their chokes, so if you try and thread their smooth bore barrels you’d not have enough metal for threads. They did make like already stated a short barrel with sights and set up for chokes and if you want to pay for the privelage they are still around.