With orders of $25 or more, Amazon offers the Walkers Shortbread Stem Ginger Biscuit 5.3-oz. Box 6-Pack for $4.19 with free shipping for Prime members. That's tied with our mention from two weeks ago and the lowest price we could find for the quantity now by $43. (For further comparison, just one box costs $11.63 shipped elsewhere.) Made in Scotland, they're suitable for vegetarians and certified Kosher.
Note: This item is offered as part of Amazon's "add-on program" and can only be purchased with an order of $25 or more. Expect this item to ship in one to two months.