Amazon offers the StarKist Chunk Light Tuna in Water 5-oz. 8-Pack for $7.09. Order via Subscribe & Save to cut the price to $6.74 and bag free shipping. (Walmart offers it for pennies more via pickup.) That's about a buck below what you'd pay in-store locally.

Be sure to cancel Subscribe & Save after your order ships to avoid being billed for subsequent shipments.

Update: It's now out of stock at Amazon; however, Walmart still offers it for $7.09 with in-store pickup.