morph an input hole shape to a different output hole shape in a solid block

[vampsthevampyre]

I'm looking to model a tape former that takes a flat tape and rolls it up into a tube around a bunch of cables. Currently this is performed using a formed sheet of tin but with the foil constantly running over this tin it is wearing it out. The idea is to take a block of steel 60 x 60 x 140mm and wire erode the former inside this block. This can then be coated with a wear resistance coating and possible water cooled. I have tried googling how to morph one shape into another but my googlefu has let me down. I have attached pictures of what we currently use and what I would like the input and output holes to look like, unfortunately its the bit in the middle that is alluding me.

I have also included a numbered diagram to show how the morph should translate from one side of the block the other

any help would be appreciated

Regards

Ian