Be patient. I suspect this is a common extra part, as many over the years have ditched their A/C systems in the name of more power... or is that, mopar?
I have one in good shape but it's off of a cast crank 440, which means that there will be one mismatched bolt hole that would need to be ovalled out slightly to fit a forged crank 383. It's otherwise identical to the original pulley on my 70 383 with a/c. If interested I can dig it out and send some pics.