ATM,
You and your brother be REALLY CAREFUL in Atlanta. It's pretty dangerous. If the weapon you are purchasing IS legal in Kali, then you should be able to bring it back with you. But I would CHECK with your favorite gun shop BEFORE you leave Kali.
If you drive and bring it back that way, check the states along the way. As it's the south, I doubt you will have any problems with all those 'pick up truck driving, gun rack, rebel flag waving' rednecks. I should know, I used to be one.
If FLYING, ship it from one firearms dealer in Atlanta to one in Kali. EVERY arline I'm aware of put REALLY LARGE BRIGHT ORANGE 'WARNING, FIREARMS ENCLOSED' type stickers.
A buddy of mine had four collectable 1911 (pre WWII) that were stolen from a LOCKED CASE (they CUT the lock off). The airlines liability? $200 per firearm. His wife even worked for the airline he traveled on. He got screwed, big time. So be careful.