Talked Mom and Dad into an H&R rifle/shotgun combo for my 13th birthday, in 1967. Break action single shot with interchangeable barrels fitting the one receiver and stock, a 24 inch 20 gauge and 18 inch .3030 barrels.

Like this one except mine isn't for sale, that is, lost in the Great Boat Wreck, take 4...

https://www.gunsamerica.com/userimages/5438/921749153/wm_2898069.jpg

https://kekpe.pe/i/5f42804634fa1.jpg