Baumi
Adventurer
Thanks for all the suggestions! 
Sadly the Implement Powers from the Bard are simply far too good to pass them up, so I will not go with Weapon Powers only (which would have been the easiest way).
I tried the Pact Hammer, but the Character Builder doesn't let me use it (tried Multiclassing and AIP). Hybrid is a bit much just for a Hammer Implement, but this should actually work.
So thanks again for all the tips, but I think I will stick with either the Kopesh or a re-skinning.

Sadly the Implement Powers from the Bard are simply far too good to pass them up, so I will not go with Weapon Powers only (which would have been the easiest way).
I tried the Pact Hammer, but the Character Builder doesn't let me use it (tried Multiclassing and AIP). Hybrid is a bit much just for a Hammer Implement, but this should actually work.
So thanks again for all the tips, but I think I will stick with either the Kopesh or a re-skinning.