Chronic Bile Duct Stones or Stricture: The patient's history of cholecystectomy and persistent right upper quadrant (RUQ) pain, along with elevated liver enzymes (AST 177, ALT 143, GGT 480), suggests an issue with bile flow. The elevated GGT, in particular, points towards a biliary or hepatic origin of the pain. Chronic bile duct stones or stricture could cause these symptoms and lab findings.

Primary Biliary Cholangitis (PBC): Elevated liver enzymes, especially GGT, could indicate PBC, an autoimmune disease of the liver characterized by progressive destruction of the bile ducts within the liver. The patient's symptoms and lab results could align with early stages of PBC.
Primary Sclerosing Cholangitis (PSC): This is another autoimmune condition that affects the bile ducts, leading to scarring, narrowing, and obstruction. It could present with similar symptoms and lab abnormalities, especially the elevated GGT.
Hepatitis: Viral hepatitis (A, B, C) or autoimmune hepatitis could cause elevated liver enzymes. However, the specific pattern and the context of recent cholecystectomy might make this less likely but still worth considering.

Hepatocellular Carcinoma: Although less likely given the patient's age and presentation, any significant elevation in liver enzymes, especially in the context of chronic liver disease, warrants consideration of hepatocellular carcinoma. Early detection is crucial for treatment.
Pancreatic Cancer: Obstructive jaundice and abdominal pain can be presenting symptoms. Although the patient's pain is localized to the RUQ, pancreatic cancer affecting the bile duct could cause similar symptoms and should not be missed.
Budd-Chiari Syndrome: This condition, caused by thrombosis of the hepatic veins, can present with abdominal pain, liver enlargement, and elevated liver enzymes. It's a rare but potentially life-threatening condition that requires prompt diagnosis.

Sarcoidosis: This autoimmune disease can affect multiple organs, including the liver, and cause elevated liver enzymes. It's less common but could be considered if other diagnoses are ruled out.
Amyloidosis: Systemic amyloidosis can involve the liver and cause elevated liver enzymes. It's rare and usually presents with systemic symptoms, but it should be considered in the differential diagnosis if common causes are excluded.