Sleeo sack suggestion and Anount of sleep

My son is 5 months old and has been swaddle free for about a month now. He used to sleep 11-12 hours a night, then the lovely regression hit. We used that time to transition out of the swaddle since sleep was a mess already anyway. Since the regression ended he hasn’t slept more than 9 hours. Yesterday he was extremely over tired so I swaddled him to help calm him down, and he proceeded to sleep 12 hours. He is rolling both directions so I know the swaddle isn’t a safe option. Does anyone have any sleep sack suggestions that might help him sleep longer?