I have only two examples of each.
It took me about 4 years to fill a two litre jar with commemorative coins only, all
taken from pocket change at face
Easy to spot, because the designs are different from normal coins.
I did not check the contents of the jar until it was full, although I was tempted to do so.
Out of this, I have formed a nearly complete type set of Australian commemorative coins of all
denominations 1970 to date.
The duplicate States sets in 20 Cents and 50 Cents are
I still put aside any commemorative coin I find; it has become a habit. When I have accumulated quite a few, I check the stash periodically, and add any coin that is not duplicate to my collection.
So keep searching. Lotsa fun!