2 eternalized sets is fine. That will give you 600% Eternal find rate chance. Based on the list I provided, try to use 2 eternalized sets, 1 nadroji, 1 epiphany and anything else for the other 3 sets.
I have completed the enslaver feat with 3 eternalized gears (650% Eternal find chance), luck 1012%, 1 Nadroji gear for ultra rate find 62.5% and have used numerous eternal maps for 149/150 enslaver feat. However, I never had an eternal pet drop on the enslaver feat. Like my notes above state, I have 1 eternal pet drop every 5,714 pets. In each of the times they dropped, I did not expect it.