If you don’t find them on any stores, you can for sure made them by yourself, or ask a specialist shop to do them (i did it a lot a few years ago).

See there :

http://www.thomann.de/fr/pro_snake_patch_klinke_winkel_030_m.htm?gclid=CMiX1qSQn70CFerpwgod8iAAfg

30 cm ! 50cm ! 60cm ! whatever you want :).

Check also the Yellow Cable, they got all