With golden South Sea pearls there are some very important value aspects that need to be considered when determining actual value. The wholesale value of the pearls in the picture is actually quite low.
First, color is extremely important when dealing in Golden South Sea. If the pearls are yellow instead of gold, the value drops substantially. Many times yellows are color enhanced to attain the coveted gold coloration, but this should be disclosed.
The shape of the pearls is also important. The pearls pictured are off-round, likely drop, as the setting is designed to cover the ends of the pearls. Drops cost significantly less than rounds, if other factors such as luster, color, and surface are equal.
Lastly, the pearls have blemishing, as noted in the description. Although the setting does a good job in hiding the inclusions, this spotting will significantly reduce the cost of the pearls, regardless of color.
That being said, the pearls still likely cost the manufacturer $40-$50 each, and the setting another $50-$60. So overall, the price really is not bad, and it is likely lower than you would be able to find in a brick and mortar jewelry store.