A lot of the early NS records can be found on the Nova Scotia Archive site.
www.novascotiagenalogy.caThis is a free site maintained by the Nova Scotia Archives. You may need to download a viewer program which is free onsite to see the actual record.
Keep in mind that there were at least three James W Marsters living in Hants Co. during the same time. One died in 1910, one in 1916 and as the below records show your James W. died between 1921 and 1946.
James W`s first marriage was to Susan Thompson in 1869. She died sometime prior to 1875
The marriage record of James W Marsters to Rebecca Wood (note: on the above NS Archive search site James W has been transcribed as James M) states that he is age 28, a widower, a mariner and son of Daniel and Abigail. They were married in Hants Co in 1875.
The 1901 Census show the family as James Marsters, age 54; his wife Rebecca his wife, age 46; Frank A Marsters son age 15 and Alace M, daughter age 5.
Rebecca Marsters died age 54 in Summerville on Sept 26, 1909. She is married at the time, according to the record, to James William Marsters.
In 1921 James Marsters remarried. The marriage certificate describes him as a widower, retired, age 74 son of Daniel Marsters and Abigail Hill. He married Rosella Ogilvie a 68 year old widow on March 16, 1921 in Parrsboro, NS. The 1921 Census records James and Rosella residing with Rosella`s son Frederic Ogilvie in Parrsboro.
The Delayed Birth Registration for John Steadman Marsters was processed in 1946. On this he states that his father is deceased. So the best that I could do was to find that James W Marsters died between 1921 and 1946.
The above records can be seen on the Nova Scotia Archives site
The parentage of Daniel Dimock Marsters can be seen on the free LDS site
www.familysearch.orgThis site provides access to lots of records and also online member trees which is where I found the record for Daniel so it is not substantiated with records, just provides fodder for research.
https://familysearch.org/ark:/61903/2:1:M7KZ-JHCHope this helps