Hand Adjustable Reamer?

Can anyone recommend a good expandable type reamer (brand name) for aircraft
work? All I need to do is ream out an elongagted hole a few thousands of an
inch but since it is an aft wing attach fitting and the bolt needs to be a
tight fit. I have seen adjustable reamers range from $20 to $60 (5/16-3/8 in
range). What are the differences? This is a one time job but I want to do it
right. I have been told that a straight flutted reamer would probably be too
big by 2-3 thousands as this will be a in field in situ job and alignment is a
problem since need to go thru 3 holes (sandwich plate and tongue) in one
direction. Thank you.

Larry