Best thing to do is to go to a Mazda dealer and order the specific part, this is not a bulk hose item. It has to be made to precise specs and often has 2 different sizes on each end. I do Emissions work in N Ca, so I see this type of thing pretty often and I have to buy the correct part.
Had this happen with my truck.... the vent and filler hose is one part and is a common failure so I've heard. I got a replacement at Napa auto parts about $200.00 when Mazda could not even get the part.