Amazon offers the StarKist Chunk Light Tuna in Water 5-oz. 8-Pack for $5.88. Order via Subscribe & Save to cut the price to $5.59 and bag free shipping. (Walmart offers it for pennies more via pickup.) That's $2 under our August mention and about a buck below what you'd pay in-store.
Be sure to cancel Subscribe & Save after your order ships to avoid being billed for subsequent shipments.