Meritline offers this AAA / AA Battery Case Holder 2-Pack for $2.99. (Click "Add to Cart" under "Buy More Save More".) Coupon code "MLCB13SN" cuts the price to $1.49. With free shipping, that's the lowest total price we could find for two similar cases by $6. Each case holds four batteries.

Of note, it ships in a random color.