So you have 1000 frames with different heads? Why don't you split them into 100 different sprites with 10 heads each?
Keep all these sprites on a separate (unused) layout, so that they are not loaded automatically.
Add all 100 sprites to a family, say "HeadFamily".
Then on start of your game layout create an instance of the sprite with the head you need.
System Create Head58
HeadFamily Set animation frame 3
This way only one sprite with 10 frames will be loaded into memory.