Preheat oven to 350 degrees. Line a cookie sheet with parchment paper. Set aside.
In a medium-sized bowl, sift together the flour, baking soda, cinnamon and salt. Set aside.
In a large mixing bowl, beat butter and the sugars until creamy, about 2 minutes. Add eggs, one at a time, and the vanilla. Beat well. Add the flour mixture to the wet mixture and blend well. Add the oats and the raisins to the dough and blend, being sure to occasionally scrape the sides of the bowl to be sure all ingredients are evenly incorporated.
Using a tablespoon, drop rounds of the dough onto the parchment-lined sheet. Gently flatten out the top of the dough, being sure not to press too firmly or the cookies will become too thin. Sprinkle the top of each round with sea salt (just a few flakes go a long way). Bake for 10-12 minutes, or until the edges and the tops of each cookie are golden. Cool for 1-2 minutes before transferring to a wire cooling rack.