I was unable to find a model for this IC. In my database there is an AMP02 that is close to this that you might be able to use. You might want to check this out to see see if you could replace your AMP03 with it for simulation purposes.
This is all I can do on this. Unless someone else has modelled this an willing to share it, then you have to either use another amp as described above or try and create one on your own from the datasheet.
Sorry I couldn't help more but this is all I have on this.
