If the S10 T5 has a cable speedo output then $250 is fair if condition is unknown. If the same cable speedo S10 T5 has been gone through and has a guarantee then $500. Rebuilt then add another $200.
I suggest that you find an S10 T5 with a 0.72 OD even if it has a VSS speedo output. Drive it and use a GPS unit to know your speed. Later you might find a rare 1988 or earlier S10 T5 with a cable speedo. That would be a good time to swap. I look for those 1988 and earlier units almost daily on CL and I usually only find 2 a year.
