Hi,
I have a SG standard with a push/pull pot for the bridge. I dont know what kind it was, but my guitar guy works out of his house and had one laying around, so I dont think they are anything special. Just get a regular pot, not a long shaft.
I think he cut off some plastic or something off the top so it fit perfect and did not hit the plastic plate. Without cutting that part off, it fit but did hit the plastic plate which when screwed down it had a little bubble in it...thanks