A good possibility is the Motorola MPX2010 series of low pressure
differential solid state sensors.  They have good performance, are temp.
compensated, and have low offset voltage. I am using them with a Burr-Brown
instrumentation amplifier, the INA-125, which is designed for use with
four-arm bridges, and ouputs a regulated and selectable bridge excitation
voltage. It has low offset  and is gain programmable with one resistor. I am
using the sensor in a 0-1 psi differential application. It has two ports -
one for positive pressure and one for the vaccuum side.  I got samples but I
think the price is on the order of $ 14.00.  I operate mine with 0-5.00 VDC
= 0-1 psid. and use an input voltage between 9 and 16 volts (automotive)
with zener diode protective clamping.
E.M. Hoyt, Hoyt Instrument Laboratory, Beaverton, OR.