Amazon.com has 64oz. Kikkoman Soy Sauce for $4.99. Add-on items require $25+ minimum (products sold by Amazon) before they can be purchased. Shipping is free for Prime Members w/ orders $25+, otherwise shipping is free on orders $35+. Thanks ArtieChoke
Note, this is an add-on item which requires a purchase $25+ in order to checkout.
You can also through Alexia and By pass the Add on Item Requirement