Put all of the meatball ingredients except for the oil in a mixing bowl. Mix until thoroughly combined.
Heat a heavy skillet to medium heat and add the oil. Using wet hands, gently form the meat mixture into balls. The mixture is very soft, so you might not get perfect spheres. Working in batches, brown the meatballs well on both sides, about 5 or 6 minutes total. They should be cooked through at this point, but you can check them with an instant-read thermometer to be sure. They are done at 165°.
Put the vinaigrette ingredients in a jar with a tight lid. Remove the meatballs to a bowl as they get done. When all the meatballs are cooked, drizzle the vinaigrette over them.
Serve over rice or on a pita with tzatziki sauce and feta for garnish.
