fresh is the biggest factor, and pretty rustic, honestly most US Americans would probably classify an authentic taco a form of salad. I'd recommend greens you like, onion, radish, and any level of chili pepper your comfortable with. as for masa A place I liked in Tijuana used to use a pancake dropper and just left it at that, no press, and grilled them to order, really just any masa you can find and water a little fat is going to be most recipes you find, but it can be challenging if you can't find someone to show you how they make them.