Peacocks from Scotland to Australia

My name is Ernest Tuff; my mother’s maiden name was Maria Peacock. She had two brothers William John and James Craig Peacock. These brothers left Northern Ireland and went to live in Renfrewshire (I believe to relatives already there) Scotland in the early 1900s. James married a Margaret Wallace age 21 of Croft Place Renfrew on the 3rd.Dec 1919 Parish Church Renfrew.

William or James had a son named James he married Josephine? They came to spend their holidays at our house every year. They had a son named James born in 1948.

James dob 1919 my cousin and his wife Josie dob 1918 with their son James immigrated to Australia on the 27th.Sept 1950 on the Cameronia, Numbers 387, 388, 389. in Melbourne 1/11/1950. But there I have lost tract.. As I was only twelve at that time it was my mother who had any correspondence with them. Then when my mother died all contact ceased.

I am now doing our family tree and would like to contact James and Josie if still alive or their son James, I think that they also had a daughter.
May someone has come across these in their search? Glad of your help
I attach a photo of Jim and Josie in 1942 before they went to Australia

My Regards
Ernest Tuff