Hello Taurisker and thank you for your time. I unfortunately do not know where it was found. Ac search
has one similar that says it's an unrecorded type but gives a BMC S 140 http://www.acsearch.info/record.html?id=490959
so I'm guessing its in their catalog of Celtic coins
but I don't have that one.
I also cannot guarantee authenticity. Under a microscope it appears weathered but im no expert. I hopefully will have my new lens for my camera tomorrow and can take a better pic to post in the authentication
section. Thank you again and have a great day!