Replacement drive cords for dynamics

[City view]

Just been quoted £35 by concept for a replacement cord for my dynamic (including delivery). I appreciate its not just any old bit of rope but this seems expensive for something which only lasts around a 1000 km. (My ex OUBC dynamic is at 8,972,113 recorded metres so presumably on its 8th cord!) Has anyone else managed to source the cord from somewhere else? Somewhere I have seen the trade name of the cord material mentioned but can't find any reference to it on the concept sites, anyone know what its called? My club has dynamics so buying a bulk spool might be a money saver.

[Citroen]

Have you tried both http://concept2.co.uk & http://indoorsportservices.co.uk for spare parts?