Kreigsmarine Narvik shield authentication

[Waffenampt280]

Good evening all!
I would appreciate some expert opinions on this shield.
I have no experience with these. I am concerned with
The lack of symmetry in the feathers.
Is this authentic?
Thank you for your time.

[Pascal H.]

Not an original shield.
There were no original Narvik shields with side tabs.

Kr
Pascal