you have multiple choices in the central area of Portugal. In Ericeira you have Ericeira Surf Shop, Boardculture, Boardriders-Tiago Pires Shop, in Peniche you have 58 surf shop, Peniche Surf Shop and many others. In Lisbon you have several stores in Costa da Caparica, Carcavelos. Just ask the locals and you'll find a surfshop in every big city around seashore.
Portugal by van.