1 mitutoyo what doesn't do sub .001"? If you are trying to measure at less than 1 thou - then you will most likely need a micrometer. Measuring at less than .001" with a vernier is a little haphazard unless you do it all day and you have good eyesight. Micrometers are certainly available to .0001" (or 1/10th thou) from Mitutoyo.
Even a micrometer that doesn't measure in 10ths can still be use to very good effect because of the spacing of the graduations. Do the homework, shop at specialist machine tool measuring equipment shops and get educated face to face by people who know what they are talking about.
There were other names mentioned as well - Starrett or Moore & Wright. If you are after a dial indicator, I will recommend Mercer or Seiko, again all to .0001".
You still have not yet stated what tools that you are after - you have merely mentioned the required accuracy.