The servo tester that I ordered last week arrived by mail today. Still no sign of the ESC from Hong Kong so I can't wire everything up, but it's a start.
I go the E-Sky EK2-0907 servo tester from Hobby Lobby. With shipping, it was $13.69 although you can get it for a few less dollars if you shop around. I just wanted a basic model and it fit the bill. Most of the units that I see on ebay are identical to this.