I have also cooked Argentine skirt steak or brought empanadas. Se below for my favorite Argentine market in Los Angeles.
I also made homemade guacamole used as a topping for the tacos. I use fresh hass avocados for a nutty taste and reed avocados for a creamer taste. Fuerte avocados also are great for guacamole. Whenever possible it is best to purchase all fruit or veggies from a local farmers market.
To make my guacamole I used fresh ripe avocados, then added hot red spicy salsa, peppers, garlic, and ciliantro to my guacamole. I seasoned it with a little squeeze of lime. See below for my recomendations on where to purchase items for your next camping trip.
Amazing Chicken (pollo asada) or Carne Asada (for tacos), Salsa
http://www.vallartasupermarket.com
Argentine steak and Empanadas (Alex Meat Market)
http://www.yelp.com/biz/alex-meat-market-carniceria-argentina-north-hollywood
Cilantro, carrots and radish (La Canada Farmer's Market)
http://www.farmernet.com/events/one-cfm?venue_id=868