I had a local gun shop order some for me last year and I think he sold it to me for $18/box. You may look into that because it could possibly save you a bit in shipping. When it's only 20 shells, every little bit off counts!
Maybe look at Gander Mountain's website. They had some on sale a while back, and I don't think they charge for shipping. I don't know what their rules are for ammo though.
Also, check out the Hevi rebates. They will send you $5 back per box (up to 4). That's a buck a shell
HEVI-13 and MAG BLEND REBATE
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