Are there inline flow reducing valves that won't make this noise? If so,
does anyone recommend any particular make?

My experience has been the opposite and turning down the isolators is
usually effective.

However, you should also check your mains static pressure. You may be in
need of a pressure reducing valve if the input pressure is much above 3 bar.
Once you start geting around 5 or 6 bar, plumbing starts to get really quite
noisy and unmanageable.

Christian.