How to find an appropriate object in array by one of its properties

The easiest way is to define a find function which takes a predicate

function find(arr, predicate) { 
  for (var i = 0; i < arr.length; i++) {
    if (predicate(arr[i]) {
      return arr[i];
    }
  }
  return null;
}

Then you can just use this method on the array

var found = find(x, function (item) { item.id === 1002 });