I'm looking to put together a set of ball bearings between about 4/16
and 1", in as small increments as possible for removing dents from
brass instrument tubing from the inside. What size increments do
readily available - i.e. "off the shelf" ball bearings normally come
in?

One supplier has said in that size range they have 16 bearings - 1/4,
9/32, 5/16, 3/8, 7/16, 15/32, 1/2, 9/16, 19/32, 5/8, 11/16, 3/4, 13/16,
7/8, 15/16, and 1 inch. I see there are several gaps where the size
jumps by more than a 1/32. I was hoping to find a set that more evenly
covers the sizes. Is this a realistic goal? I'd like to find them all
at once instead of piecemeal it together so it would be worth the
time/bother for whoever sends them to me.

Would I be more likely to find a greater number of increments in metric
or inch sizes? In fact, if I included both metric and inch sizes, would
that be likely to fill in "gaps" in sizes?

Thanks for all input.