I had the same question, whether there were 3rd party solutions to the impending totally-scrambled digital signal. It's happening nationally, and in monitoring some national discussions of a 3rd party box, nobody has come up with an idea better than the suggestion to get a tuner with a cable card rented from Cox, which appears to be cheaper than the after-a-year monthly price of the new cable boxes they are renting. In this thread, someone mentioned TiVo, which is an example of a situation where you own the box but plug in the Cox card. I have one (the TiVo Roamio) and it works great 95% of the time but does require an outboard box ("tuning adapter") that is included in the CableCARD price.
From Cox site (https://www.cox.com/residential/pricing.html):
Rounded figures: CableCARD, $2/mo.; MiniBox, $3/mo.
Example of fruitless national discussion on search for alternate one-time purchase solutions:
And then there's the "put up an antenna" solution, of course, if it just the local channels you want. If you DON'T have multiple family members wanting to watch different channels and just want your show in any of several rooms, you can hard-wire a Gemini Rabbit VCR/Cablebox distribution system or something similar where all your rooms can get the signal from one Cox cable box output (FCC shut down Gemeni's local-wireless broadcast device). I had a Rabbit years ago and it worked fine with Fairfax Cox service until a growing family needed channel diversity in each room.
I haven't seen these kinds of discussions branch much into streaming but I do like the flexibility to watch many of my Cox-fed shows on the computer, and with an iPhone you can probably transmit it to a Chromecast. I watch my Cox CNN at the office on a federal computer, and my Cox-supported HBO on a Roku, which like Chromecast is an internet device that plugs into an HDMI port on a TV (and I have had limited success with the Roku to an old TV that has conventional RCA ports with an HDMI converter).
It's a brave new world of options, but a core principle is that Cox has you by the short hairs to get their cut. I blame the Fairfax County Board of Supervisors for not writing "free analog basic cable to all sets in a household indefinitely" into their contract with Cox when as Media General it got rights to ROW and exclusivity to wire Fairfax County years ago.
Apologies for the long post.