If you can't find the M615, then go for the new M6000 which has replaced them. Still dirt cheap, found under 100€ new and below that from Hongkong/China on the bay for f/r combo and then just add rotors of your choice.
@Viggen started
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If you can't find the M615, then go for the new M6000 which has replaced them. Still dirt cheap, found under 100€ new and below that from Hongkong/China on the bay for f/r combo and then just add rotors of your choice.