I assume you're not looking for test indicator, correct?
If you want American, the usual choice is Starrett (B&S are rebadged Kaefers, to the best of my knowledge.) Some claim that the Starretts are made someplace else, with enough assembly being done here to be stamped "U.S." Don't know if that's true or not, but it wouldn't surprise me. That's because they (IMNSHO) were never very good, and have only gotten worse with time. Current models are sorely lacking in quality even compared to the so-so models of 20 years ago. I can believe that they come from overseas. That being said, if all you need is to be within a thousandth and don't use them everyday, even a Chinese or Taiwanese indicator will be more than sufficient.
It goes something like this: if you want the illusion of being U.S. made and don't need the quality, buy Starrett. If you don't need the quality and aren't fooled by the stamp, buy a Chinese/Taiwanese model. If you really want it to be made here, get an Ames (supposedly; I've not seen one.) If you want quality, are capable of using the tool to that level of quality and are willing to pay for it, get a Compac.
Finally, if you want good quality at a good price - sort of a best of all worlds - get a Mitutoyo. (This is hard for me to admit, as I generally hate Mitutoyo stuff, but their dial indicators are really good and a bargain for what you get.)