That's about the size of hole a 6mm reamer will produce and that should be readily available in the USA.
If you really need that level of accuracy then Metric reamers are available in increments of 0.01mm so a 6.01mm may be nearer as they often cut slightly small. You may have to get a machine type as the tolerances on a hand reamer are often looser and you probably won't get that level of precision by hand anyway!
Trevor Clarke. (R & D) Scientific Instruments.Somerset. UK