ok.. so i ordered singer 29k bobbin case and modified it to work with my cl 17. With some power tools it took me about 20 mins. You just have to grind out red parts on picture. Working well.
i'm trying to find bobbins as well, but with no luck so far.
Also, did anyone try to fit Singer 29k small bobbin case into durkopp cl 17-1-1? It look like it have similar dimensions.