Don’t know much about these coins besides it is very limited due to the signature and the dolphin mark I believe. Any info would help
Just so you know.. There is a World Coins forum on CoinTalk. It's for Foreign coin questions. This forum is fine but the other would probably be better. Just a suggestion Did you try Numista?
The Dolphin is a privy mark used 1974-1994 for Engraver General Emile Rousseau https://en.wikipedia.org/wiki/Oscar_Roty
I have posted my O. Roty coin several times. This has his initials doubled. Large scratch on the reverse but I like it.