It was 13.62 plus handling charges. Total cost per mag was $16.61.
When I saw the price change I called Cheaper than dirt. The Operator confirmed the price and handling charges. They denied that i$10.92 was an advertised price. It was also to be shipped from the warehouse (C) which was indicated in the add. The company charges different prices depending on the warehouse from which the item is shipped.
My LGS sells the same mag for $16.60. Since I am in AZ I must pay local and state sales tax on internet purchases.
In my message to the Customer service I pointed out that this practice is not only unethical but illegal. I wait to see how they respond.