Try searching on ancestry.co.uk as they have millions of war records. If you know G J Brine was a casualty during his service you can search for additional records from the Commonwealth War Graves Commission on cwgc.org I believe it is also possible to search the Imperial War Museums records. Know though that the government keeps many records secret untill a certain time has passed.
A Royal Marine service number is a unique identifier assigned to each member of the Royal Marines, the naval infantry of the United Kingdom. This number is used for administrative purposes, including record-keeping, personnel management, and tracking service history. It typically consists of a combination of letters and numbers, reflecting the individual's enlistment and service details.
The Royal Mail Service is a postal service in the United Kingdom. The Royal Mail Service was established in the year 1516.
A. D. Fleming has written: 'Record of the First Volunteer Service Company' -- subject(s): Royal Warwickshire Regiment
Royal Maritime Auxiliary Service ended in 2008.
Royal Marines Band Service was created in 1903.
Royal Naval Air Service ended in 1918.
Royal Naval Air Service was created in 1914.
Royal Army Service Corps ended in 1965.
Royal Army Service Corps was created in 1888.
Royal Canadian Army Service Corps was created in 1919.
Royal Netherlands Navy Submarine Service was created in 1906.
Royal Norwegian Navy Air Service ended in 1944.