You say you have alot of AR-15mags? If so get a mossberg mvp predator. It's a bolt action .223 that takes AR mags.
best advice so far... I was looking at these myself
I'm partial to lever guns over the semi's anyway, so you are already too late to get ahead of the panic on the semi's, get a lever gun ( more likely to find ammo now as well ) the mention of the Marlin is not a bad idea, as the top of the reciever is solid, allows a longer sight radius for iron sights, or the easier mounting of a scope
that said... a couple comments... the newer mini's have been better on accuracy, but if you buy used, they were made for several years, that were actually poor in the accuracy dept.
but also most of these type rifles can be made at least reasonably accurate... I have an $89.00 Chinese SKS ( anyone remember those ) that has been accurized to where I can actually put 10 rounds on a 3" spot at 200 yards from the prone position...