Rheostat/Potentiometer

Hi,

I'm working as a Biomedical Engineering Technician intern in a local
hospital and I need help finding a rheostat or potentiometer that can
meet my needs.  I'm looking for a linearly variable resistance device
that goes from 0 to 150 ohms, can handle between 1.5 to 2 amps of
current, and that has a very smooth (granular) change of resistance as
the wiper is rotated.  Resistance changes of %4 or more would not be
acceptable?  I have spent hours looking for such a device.  Any
pointers?

Thanx,
Ed