Probably very few, yes.
I've seen similar with probably only 2 - 5 sticks made.

I can't recall if Gene Trimble turned up some info on Pat Sullivan while researching something else that I forgot about. I don't see it on my site right now.
As far as I recalled, when Christy Jones was 'broken up' and Paul-Son was formed, they bought the rights to the mold. Maybe Sullivan had temporary ownership somehow during that transition.
No-one else ever owned it and it never moved from its original physical location at Burt Co (manufacturer) in Maine until it was finally handed over to Paul-Son when they opened their own factory.

Gene will no doubt read this post and reply