Walmart offers the UPG AAA Heavy-Duty Battery Value Box 50-Pack, model no. D5323/D5923, for $6.97. (Amazon charges the same with free shipping for Prime members, although it won't ship for two to four weeks.) Opt for in-store pickup to avoid the $5.99 shipping fee. That's 14 cent per battery and tied with last week's mention as one of the lowest per-unit prices we've seen for AAAs. (It's also the best deal we could find for this pack by $8.)
Update: It's now out of stock at Walmart; however, Amazon still offers it for $6.97 with free shipping for Prime members. It's expected to ship in two to four weeks.