I would quess that cheapest place to buy those materials is one of the nearest boat building shops:
massachusetts boat builders - Google Maps
Ring few of them and see if they are willing to sell the materials. Tell them what you are building first because they like to know it has helped when I have asked materials. Usually you get the materials at least half the price. They can also give better estimation how much materials you will be needing for your whole project.
You were first building that 1:4 model and after that 1:1 model and on both cases you first make glasfibre molds/tools?