There are around 20 easy enemies in the prologue. Play through the game once to get as many as normal (I got about 750, but that was with some intentional grinding), and then just do "Chapter Select" and choose the prologue. You can get through it pretty quickly when you learn what training tips you have to accomplish. You get 20 or more each time through the very short prologue, so it's easy to grind the rest of the way to 1000 like that.
You could also beat the prologue and then chapter select it over and over right from the start, but then you have a very long ways to go to get to 1000. It's more fun to at least play through the game once.