Just pop into a NZ safety shop or the like, get someone to let you try on a couple of there grade 5+ options and choose the one that seals around your head the best. Maybe take your rifles stock (not the whole rifle!)with you to make sure the cups don't interfere-i never have a problem with this but enough people do that it's something to consider. Make them give you trade price and you should get something very good for $50
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