Hello,
Like Philippe, unfortunately Val, your badge is a reproduction.
Why?
Because:
---The eagle is a Prussian Reserve Landwehr eagle from which the Prussian Landwehr cross has been detached. You can see the four weld holes, which are not present on genuine Brunswick Reserve eagles.
--The badge lacks the details of the authentic ones; in particular, the Landwehr cross is straight on the upper arm, whereas on authentic badges it follows the curve of the grooved crown.
--The Landwehr cross is attached below the "alter Art" active duty badge, whereas on authentic badges it is a single piece.
--Authentic badges are always screwed on. Copies are specifically designed with welded tabs, which prevents access to the reverse side to detect the forgery.
The badges shown by Brian and Philippe are perfect.
And here is a copy:
These are cast electroplatings and not stamped, the screws are fine, and the LWK is part of the plate, but the top tab does not follow the curve of the grooved crown...etc...etc... In addition, access to the reverse is undeniable.

Finally, here's a near-perfect replica. Even the screws are very good. The only remaining issue is the LWK, whose top tab is still straight! But there's cause for concern!

Once again, for those unfamiliar with the subject, if you can't identify a counterfeit by looking at the front, you absolutely must examine the back. Personally, if you can't do that, I don't buy it...especially not from 3000km away via teleshopping or on Line E-Bay etc...
Sorry, Val. I hope you didn't pay too much for it.