Southern Ohio Gun is advertising surplus M2 ball 30.06 Garand ammo for $99 for 270 rounds loose in an ammo can.
I say "possibly" because they don't say where it's from or condition but it's a lot cheaper than anything else I've seen. If you're running low, you might want to check it out.
http://www.southernohiogun.com/ammun...plus-ammo.html