i quickly knocked up a simple puller for that job by using a bit of 5mm plate steel and cutting it triangular the drilled holes same spacing as the mower magneto holes and one centre hole. i got 3 bolts same thread as the housing and one for the centre hole to allow some leverage space.
it worked so well i made another for the older victas as their hole spaces are a little bit different. i keep the lot in a plastic container ready for when i need it.