Being concerned about over the counter ammo is a no brainer. The counter today is your keyboard. Figger out which cartridge appeals to you most and buy a rifle so chambered. Order some ammo online, several boxes if it helps on shipping, and go shoot. Personally I have over the years gone from 30-30 to 30-06 to .270 Weatherby Mag and now am enamored with the 7mm-08. Wife uses same cartridge. Son started with a .260 and I've shot a few with it and also a 6.5x55. Son has also done a lot of damage with his favorite, a red pad Ruger 77 in 7x57 and another in .270.

As free advise I'd recommend the 7mm-08 even though local ammo purchase is limited. Order a few boxes of Hornady 139 gr Interlock ammo and go kill deer. You can spend more money on other brands but it won't kill any deader, deer wise, than that humble Interlock. Another favorite is the 140 Accubond. If you start to handload the 120 Barnes is wicked. For the parameters you quote the 7-08 is hard to beat.

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