tyvek is a building material, feels like paper.. you see houses that are being constructed covered with it for protection. some people get it at junk shops here but i heard some places that specialise in printing might also have them..since they sometimes use it to make flags.
i had a colleague who made a paper dress using old home-sewing patterns instead of newspaper.. she layered them, it was a mixture of papier-mâché
is the dress going to be sold? i think newspaper's gross tbh. and it will degrade in time, quickly... it's the way it's made. the inks, the low quality paper. for something cheap i'd prefer to use sugar or rice paper. even layers of toilet roll looks nice (if it's one layer, it will just fall apart)