The photos featured here are all from Amazon — click them and you will get right to the listings. Note: They are affiliate links and earn me a commission if you buy. The two photos above: The smaller fixture.
Above: The larger, four-bulb fixture.
Available at a number of retailers — shop around to compare prices
Amazon is just one place to find these lights. A quick google search turns them up for sale many retailers.
At Practical Props, where I first saw them, the price for the three-light fixture was $275 plus shipping ($25 to my house, the calculator said). Practical Props also has some additional photography worth checking out.
Bottom line, there seems to be plenty of opportunity to shop around.