"SRBs"? "Page 12s"? Are you going to translate from the Arabic?
Arabic?
SRB - Service Record Books - All paper items on soldiers, in this case, they were Marines.
Page 12's are disciplinary actions taken against military personnel. They are recorded on a particular form, and IIRC, it was the "Page 12" entry.
Of course, then (early 1980's) as now, it was recorded electronically in computer files, but the books were sent out when a Marine would deploy, either temporarily or full active again. The SRB includes induction, physical exams, promotions, pay notes, adjustments to records, etc.