where you may find a double pulley was on alternators and generator
if you could give us a link to apicture of your pump it may answer a question. does it have a pulley that is pressed on the shaft or held on by a nut? do you have an orig 235 p/s bracket or is it a made up one. I take it that your p/s pulley does not line up with your c/shaft pulley
canadian pontiacs also used 235 and 261 engs up to 62
ron