Two options for you:
40 x Hario V60 Size 2 Paper filters
25 x Sibarist filters
Whats the difference? The Hario filters are the standard paper filters everyone knows and loves. They produce a great result in your cup. The Sibarist filters on the other hand are a fast premium filter that helps achieve simply phenomenal results by allowing the user to grind finer and therefore increase surface area of the coffee and allow for more extraction and flavour potential. It will make you rethink V60 brews completely.