It's no secret 3D is dead. I understand you have the hardware for 3D, but you're limited to anything to be released on a 3D Blu-ray disc. It's kinda like analog enthusiasts limited to anything to be released on vinyl.
You're still in luck, however, because all Blu-ray players released in 2017 still play 3D discs...but, in case you'll try to "future-proof" your set-up, 3D will not be available in the Ultra HD format. If your TV, or new player, has Internet access, Vudu has 3D content at https://www.vudu.com/movies/#search/3d. But, then again, you have Internet problems.
HBO, Starz and Cox pulling out of 3D were an economical choice because it required 2 channels. If they offered a 3D version, they also had to offer a 2D version. Also, the limited number of people watching their 3D channels didn't justify the costs.
We do apologize for the inconvenience. At this time, we are no longer offering 3D programming because most networks are no longer broadcasting in 3D now. I have checked and it does appear that some streaming services do offer 3D programming. Please check online into what would suit you best.