They look very similar to these from Am.uk -
https://www.amazon.co.uk/XO-Optical-...%2Bcables&th=1
Most people seem to like them, and they come in different lengths if you want. However, I think I've got some of those - perhaps bought from eBay too - and the cable is very stiff. Not a big problem for me, but some have had issues with that. The stiffness also presents a problem if you want the cable to go round bends neatly.
I've not always been convinced that there's very much to choose between cheap and expensive optical cables - it's quite hard to see why it should make a difference - though I think there are factors which can influence the sound - possibly slightly. I thought that there was generally a view that it was better to go wired coax than optical Toslink. I have both and use different connections from time to time.