I thought this was common knowledge but have since realized it's not so I pass along to you the knowledge that, yes, Perma Party Balls are to be found in the AE from time to time.
I never found them before because for some reason I have to search for stuff that is level 0 - 0 instead of level 0 - 40, which is what I was doing before... Passing that along in case it's useful, as well!
Upon first use of my perma party ball, and the application of various other elements, a crowd was forming in no time. Good fun!
We can't have good news without bad I guess and that is that they are self-only : /
Bonus points, they don't bind and can be used while flying or acrobating. Got mine for 100g on the first search. One was for sale for 90 but I wasn't fast enuff..the person who didn't know they existed but knew how to search for them when I told him they do..was.