Output Inductor for class D

Hello forum, i'm new to classD and my most serious question is how i will end up with what core i will need for my amplifier.

have the necessary equipment for the necessary measurements such as a µH - mH - H meter. I read through the forum various suggestions for making the output filter but I can't find serius suggestions about core.
i have transformers from computer power supplies like EI33, yellow filter cores
and much more. so what is the best for core?

My design is tuned about 200kHz with lm311, differential amp for level shift with 2N5401 - IR2110 - IRF640