Here is a quick page of various resources for the Polymoog. It will be updated as I get more. I know some of these are getting harder to find as time goes on (or, simply scattered in many random corners of the internet).
Quick shoutout to MartyMoog and Jareth (Synthpro) for helping me on Polymoog issues over the years.
The traditional DIP packages for LM301 are no longer manufactured (much like the 5823 divider chips), so a modern SMD to DIP translation package is needed:
The Polymoog uses twenty four 5823 divider ICs, sometimes (usually!) these can fail over time. Best replacements are available from FlatKeys, you can of course make your own but these are incredibly convenient in a pinch: