Still looking for my dad's birth family...his bmom's name was ALMA. His DOB 8/7/53

I am still in search of my dad's birth family. He was born August 7th or 8th 1953 in Panama City, FL. He believes his bmom was from Bainbridge, GA and her 1st name was Alma. (He received paperwork from the court stating only a 1st name, no addresses or other birthdates for other relatives). There were however 2 girls that would be his half sisters (Alma's daughters) that were quite a bit older then my dad, maybe 6 or 8 when he was born. His bmom was a widow, and his bdad was a friend of Alma's who quite possibly had his own family. We have been told that her previous husband that had died was a trucker, but in my dad's adoptive family stories regarding his adoption changed just about every year. I would really love to know my background and my dad's biological family and I feel that since the adoption took place in 1953 I am probably running out of time. Anything helps.