With the genuine KTM thermoswitch retailing at £42 and even the BMW near-identical switch (not quite the same temperatures) around £25, here one for £18½ delivered:
http://www.carbuildersolutions.com/uk/fan-switch-100c95c-m14-x-15
http://www.carbuildersolutions.com/uk/fan-switch-100c95c-m14-x-15