basically any slicer will let you do this.

You can change any aspect of the size of a model and also how many shells and the amount of infill you use.

I think reprapper tech made the skin coloured flezible filaments.

ideally you want 2-3 shells and probably 10% infill. Given the shape of an ear you it might look abit weird with just 2 shells. but it's the number of shells that control to a large extent how stiff flexible filaments get.

But sounds like it should be doable in the slicer.

What slicer are you using ?