Pixel Dots for sure. Then attach controller and PSU of your choice and whala. Each dot is 3-4 channels so plan accordingly.
EL cheapo way get some 50/50 tape and cut small section in a circle as best you can. Then just daisy chain with black wire to next section. Lot of soldering though. Definitely won’t have a clean look if that does matter.
There's a lot of pixel string options at kutop.com Has anybody ordered from them? I never have because there's a minimum quantity for everything (I think 5 or 10 if I remember right) and you find out halfway through the checkout process. I have wondered if other distributors are purchasing from Kutop and reselling, but they may be purchasing from the same manufacturer or somebody could be copying somebody else's products. Hard to know.