Does your inlet manifold gasket to suit Ecotec and L67 supercharged include the gasket for the rear of the intake manifold?

If you are referring to the 2 orange strips with the black stripe that sit at the front and rear of the lifter valley then yes. These can be noted in the image in the link below:
http://www.maceengineering.com.au/epages/shop.sf/en_AU/?ObjectID=1469584&ViewAction=ViewProduct