Have you tired the www.thefirstgensite.com go to library and search out the year. Most of the service manuals from GM lists the engine and distributor that came with them: the 230 cu in. 165 HP ZK,ZN used dizzy # 1110396 165 HP ZS,ZM used dizzy # 1110391 I could go on and type the whole list but it's best for you to research it out and for the most the part numbers are good. You will not find these numbers in a NAPA store or Auto Zone, they were GM delco and yu should be able to locate them used.
