Have a muzzle break put on the rifle. That's your best option. And I 100% hate having one on a rifle just personal opinion.

7 mag is not a huge factor in free recoil. It has a little more than a 270. win or a 30-06 but not alot more. It's how the gun fits you and how your holding it. My native american cheeks don't like any raised cheek pieces or severe drop in comb stocks. They BUCK not PUSH. Straight stocks push and put all the recoil on your shoulder. For me that better and I don't flinch from the shoulder but I do flinch from having my cheek get sore. I've sold some mighty fine rifles that I couldn't take them smashing my face. I won't put on a muzzle break myself. I've had a remington ADL 300 win mag punch me harder than any rifle I've ever shot. And shot a friends 7mm 08 in a Howa that was purely kicking alot harder than that caliber should be kicking. My point is some rifles no matter how much free recoil they have feel like they have twice as much.

Options.
Muzzle break
Recoil pads
Mercury inserts to weigh the gun down.

OR BUY A DIFFERENT RIFLE THAT FITS YOU.