As you probably know by now, Banshee Masks are awesome in the new Eldar codex: Causing fear and denying overwatch.
So it's only logical to want one on an Autarch, right?
The problem is that Games Workshop, in their finite unwisdom, released a new plastic Autarch with only Mandiblasters, and only left the Finecast Autarch with Mandiblasters in the store while letting the one with a Banshee Mask drop out. That means there is effectively no Autarch model with a Banshee Mask available.
And since the heads of Howling Banshees are molded onto their bodies and have a lot of hair around the back of their neck, there is no easy conversion without Green Stuff with them either.
So the big question is; where to get a helmet that looks like a Banshee Mask and fits easily on an Autarch?