Wheel magnet compatibility?

[FOG]

Are the E8000 wheel magnets compatible with any other manufacturers?
I need one for a spare rear wheel and can't find a Shimano one locally. I can get one from Bikester but that will take at least 10 days and I was hoping to use it this weekend

 

[FOG]

Okay, i will answer my own question. My LBS couldn't answer my query either but a helpful staff member found a magnet that was labelled 'Yamaha' for £8 . I thought I might as well give it a go and sure enough it works fine. Presumably most wheel magnets ARE compatible.

 

[R120]

IIRC any one will work, however the key thing is the distance the magnet sits from the sensor on the chainstay - there is a tolerance it must sit within