These guys right here are a pair of spear points from Empire Knights and an Aquila from the IG vehicle options sprue. These are the beginnings of a more characterful weapon.
I removed the rear portion of the hammer, and the eagle head from the bottom of the haft.
The eagle was removed from the end of the haft.
I attached both spear points to the opposing ends of the hammer, they give it a really baroque, straight from the Heresy look. I cut the aquilla in half, folded it over and glued the two halves together for a double sided aquilla sticking off the back! Pretty happy!
Wait 'til you see the shield I'm scratch-building for this beast!