We need to do some simple hydrotesting of some new design refrigerant
piping and similar. The new refrigerants run up to 500 psi under certain
conditions, we would like to to 4x testing for safety ie 2000psi. This
is on the design side, looking for the obvious failures, will have the
whole thing tested by a lab when we are done.

At a previous place I worked we had a simple hand pump with a pressure
gage. It looked like a heavy duty grease gun with a pressure gage on it.
Any suppliers for such things these days? I could do the same thing
with a porta power hand pump but using oil is such a mess to clean out
of the pipes.