50 custom magnets for $39.13 AUD with free shipping.
You might be able to get it cheaper paying in Canadian Dollars, ($36.25CAD).
I haven't purchased these before, but Stickermule's other products have been very good quality for me.
50 Custom Magnets for $39.13 (Normally $109) (with Free Shipping) @ Stickermule
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i got a few stickers a while back and then i used magnetic paper to turn them into magnets, worked out pretty good