After about 3 weeks of crusing all the gun stores I have come to the conclusion, some might need a backup plan.
MBR alternatives. Garands are still around, and 30-06 ammo is still on the shelves. Good bolt gun in 30-06 is also a must. There is also the BAR and the Rem 742, 760, 7600 designed weapons. At one time someone made 10 round mags for the Remys.
Assault Style alternatives. Lever guns in 357/44mag/45 colt style or 30-30. 10 rounds and one can get handguns to match except for 30-30. Also short barreled Remys and Browning autos in shorter calibers. Also the Ruger 44 carbine (auto) would work.
Abundant ammo I've noticed still on the shelves in common calibers: 303 Brittish, 30-06, 270, 30-30, 243, 38 special, 357, 44 special, 44 mag, 45 auto hasn't ran out either as well as 40 sw which is supprising. 9mm was in short supply, especially cheaper ammo. Magnum rifle calibers are also unaffected.
I sold a Garand several years ago, and now wish I had it, can get an abundant supply of ammo without reloading.
For someone just getting into prepping and gun acquisition, the above are suggestions since ammo supplies have been unaffected by those who waited so late to stockpile and prep.