Well there's:
-Minion/Wind-up version of all the Primals from ARR, HW, and SB
-A bunch of different Chocobo Chick minions
-Cactuar Cutting
-Wind-up Tonberry
-Fenrir Pup
-Atrophied Atomos
-Toy Alexander
-The Peridot and Heliodor Carbuncles
-Wind-up Ixion
-Eden Minor
-Wind-up Magus Sisters (They're not the Sisters from X though)
-Wind-up Anima
-While not past summons, there are two past summoner minions in the cash shop: Wind-up Rydia and Wind-up Yuna