Just curious if you've made any headway in your search? If not, don't give up.
After a 7 year search, I found my husband's daughter. She'd been put up for adoption shortly after her birth in 1967. That was in England and I'd been searching from Ontario. Her half-brother had been searching for her and we made contact first, then with her the next day.
Also 11y search, found my uncle's (b.NS) daughter who we'd known was born in Seattle Wash. c1951-52. Parents were briefly married and he'd had no contact with her since divorced in mid-1950s + plus [my uncle] had died in 1970. We had little to go on .. but still found her.
Another 11y search for my Mum's first cousin who had been shipped out to Australia from Scotland alone at age 15y, in 1924, eventually led to contact with his 6 daughters.
Don't give up & leave no stone unturned!