How can I find out which lower end graphics cards support CUDA?

You're stuck between a rock and a hard place at this point. Your GTX 760 Ti (which is actually an OEM-only exact re-brand of the GeForce GTX 670) is already in legacy support status, with only critical security fixes and absolutely no compatibility fixes whatsoever. Nvidia announced the pending EOSL (End Of Support Life) of all Kepler desktop GPUs beginning in October of 2021, with only critical security fixes being released for "newer" driver versions for that generation of GPUs until September of 2024.

And if you ignore that and use that GPU anyway with the latest currently available version of Premiere Pro, you will receive a compatibility warning stating that "Your graphics card will no longer be supported in an upcoming release. Please update to a newer graphics card." This warning is new to Premiere Pro; previous versions would simply warn about an unsupported graphics driver. And this new warning shows that Adobe is tightening its grip on the age of the individual components. Newer versions of Premiere Pro will no longer run at all if your hardware does not meet minimum requirements because Adobe has currently depreciated its software-only MPE rendering mode, and the software-only mode will be completely removed in a future release of Premiere Pro.

And if you have to buy a new GPU right now, I would recommend neither of those two GPUs that are now more than six years old because their performance in CUDA applications have not aged well at all in that amount of time, and that their prices (though less than when they were originally released) is now higher than their performance justifies. In fact, in GPGPU performance your planned GTX 1050 is actually only about equal to that of the latest Intel integrated graphics in the 12th- and 13th-Gen CPUs! Not worth paying any amount of money for nowadays.

Instead, I will recommend a GeForce RTX 3060 with 12 GB of VRAM at a minimum for Premiere Pro.

Moved to the Video Hardware forum.

I upgraded my computer last year (12th Gen, new MB, 2-980 pros) but I couldn't and still can't bear to pay the outrageous prices GPUs are going for. I'm still running my GTX1070, and it is working fine. So, yes, the 10xx series is still supported. No guarantee how long that will continue.

First you need at the least 4GB of vRAM on the card, I would suggest at least 6GB.

Second, I would not go earlier than a 2000 series card at this time. They're already a couple series past that.