Separate existing artwork into layers via Gimp or Photoshop etc

I am a toy customiser. In order to create packages for our custom toys I need someone to use an take an existing box art work and separate them into layers, convert them into Jpeg files and send them to us individually. I am doing this so that I can easily change colors of certain layers when creating new toys so that the packages look different and we can put our custom toys into boxes.

This would involve some color filling and image sourcing. I have an original box that I can scan and email the images to you but it has been damaged where it's been opened so you will need to fill in the gaps basically.

This would probably take about 3 hours or less for someone experienced in this field. If you have any questions please ask!