......and buy your own 264. Then you'll have both without desecrating your Dad's rifle.
"And it'll kick less than a 7mm Rem Mag "
I don't think there will be enough difference to notice. A 140 grain bullet at 3200fps pushed by 58 grains of powder won't recoil much more/less than a 140 grain bullet at 3200 fps pushed by 60 grains of powder regardless of the 0.020" difference in diameter.