Preheat the oven to 425 degrees.
Split each pita in half so that you have two full discs.
Brush the pitas generously with olive oil on BOTH sides.
Sprinkle each side with sea salt to taste.
Cut each disc into 8 triangles. I used a pizza cutter for this, but you can use a knife.
Place the pita on a cookie sheet.
Bake the pita chips for 5 minutes checking frequently. Mine were very brown at 5 minutes, but you may need more or less time. You may also need to flip them over with tongs, although I did not.
Prepare the guacamole while the chips cool.
Cut each avocado in half, removing the pit.
Scoop out the avocados with a large spoon.
Mash the avocados. I used a potato masher, but you can use a fork.
Mix in the finely chopped red onion, juice from 1/2 of a lime, and salt to taste. My avocados were particularly small. If you use larger avocados, you may need to add more onion, lime juice, and salt.
Guacamole doesn't store well (it turns a gross brown rather quickly), so you should eat it shortly after making.
Store leftover pita chips in an airtight container.