I have no idea if it's original or repro - someone else up here may be able to help with that. But I do like the look of it. According to Flying Tiger Antiques it's a: Very Rare British-Made WWII Polish Navy Cap Badge.
https://www.flyingtigerantiques.com/...cap-badge.html
Also have a look here - may have some info:
http://www.warrelics.eu/forum/polish...eagles-1980-4/
Hope this helps.
Regards
Gary