Ruger Mini-14 and Mini-30
Natchez has boxes of new factory loaded 5.56 American Eagle ammo for $299.95. 1000 Rounds per big box.
Not exactly match, but if you want a bunch of plinking or back up ammo, that is some of the cheapest I've seen factory 55 grn 5.56 in a long time.
Best Regards, John K