Best Source is Enco, unfortunately don't have a phone # or a catalog at hand
and they probably don't have a WWW but you might check.

Enco sells real quality, B&S and Mitutoyo, (either loads better than
anything even Sears will sell you) BUT they also sell all the way down to
cheap ex-eastern block and then bottom of the line Chinese.  I have a set of
0-125mm mics of the eastern block issue, they were about $100 for 5 mics
with standards 2-3 years ago (Mitutoyo would have been quite a few hundred
more.)  I bought them at the rec of a machinest who had a set, checked them
and their standards in our directly traceable standards lab, they all came
right on at a light click of the click thimble, and I use them lightly for
VW work.  For this they are more than sufficient and an exceptional value, I
understand the cheapo Chinese were equally suited for light use and in fact
even hold up relatively well in a production machine shop.  They are not
particularly well finished, the markings are not as nice, they don't run as
smoothly, but they are square, repeatable, probably won't change unless you
drop them, and the value is incredible.  Yeah you get what you pay for, but
ask what exactly you want to do.  Enco sells everything, from tools, to
equipment, to measuring.  I also purchased a mid level ($30) set of snap
gages, and a 0-1 and 0-2" dial gage, magnetic base, etc. at the same time.
All work well enough for what I paid.  Generally Enco sells top of the line,
mid grade, and cheapo, it is probably wise to go for the mid grade most of
the time.  The Harbor Freight stuff are the same chinese tools and on the
American sets were I think .001 not .0001 accuracy, though they may have
upgraded as the only difference is of course the vernier scale on the
barrel.

John
janderson@iolinc.net