Some dishes had a leveling technique, where you install a reasonably vertical pole...
Then drop a larger pole with the dish, over the smaller one.
If I remember, the big 10' dish Stogie had, was made that way...(?)
I think the trick was, you have screws at the bottom of the outside pole to fine tune it to be perfectly vertical.
The inner one isn't so critical, and if over time, it moves, you can still adjust.
You might look and see if that was used on yours.
Or, as you say, maybe someone just slipped a bigger pole over an existing one, as an upgrade to take a dish with a bigger mount.
Let us know (with pix) when you get down to it.