Thanks for everyone's responses and suggestions. I emailed them at cox.help@cox.com and got a more hopeful response. The current story is that supposedly CableCards can no longer be shipped direct to customers, and have to either be picked up at a Cox location or installed by a technician. Full response is below. If true, then the Chat agent was just misinformed.
Not sure yet whether this helps me much, as our local store said they no longer stocked them, and the nearest other stores are 1+ hour drive away.
We'll see how it goes. If I get any more concrete info, I will update this thread.
Full response from Cox email support:
I apologize you are having this difficulty. It sounds like the agent you chatted with was misinformed. I read through the latest process for installing cable cards, it says that we still offer cable cards, but we are no longer able to drop ship them, They will need to be picked up at a Cox solution store or installed by a Cox technician. I apologize I'm not able to create an install work order to add this equipment within my department but if you call our sales team they will be glad to get this set up. Im not sure why the agent at our store told you they were no longer available. I'm certain the agent you speak with when you call in will be able to walk you through these steps. The best number to call is 1-800-234-3993 Monday - Friday, 8 am - 9 pm or Saturday, 9 am - 6 pm