Peptic Ulcer Disease: The patient's symptoms of epigastric and right upper quadrant pain worsening with eating are classic for peptic ulcer disease. The age and presentation make this a highly plausible diagnosis.

Gallbladder Disease (Cholecystitis or Cholelithiasis): The location of the pain in the right upper quadrant suggests gallbladder pathology, especially given the association with eating, which can trigger gallbladder contraction.
Gastroesophageal Reflux Disease (GERD): While GERD typically presents with heartburn and regurgitation, some patients may experience epigastric pain, especially if eating exacerbates symptoms.
Hypertension-related Symptoms: The patient's elevated blood pressure could contribute to headaches and potentially to abdominal discomfort, though this is less direct.

Myocardial Infarction: Although the pain is epigastric and right upper quadrant, myocardial infarctions can present atypically, especially in the elderly, with pain referred to the abdomen or as epigastric discomfort.
Aortic Dissection: This is a life-threatening condition that can present with severe, tearing pain that may be referred to the abdomen, though it typically starts in the chest and radiates to the back.
Pancreatitis: Acute pancreatitis can cause severe epigastric pain radiating to the back and can be associated with eating, especially if the patient has recently consumed a large or fatty meal.

Carcinoma of the Stomach or Pancreas: While less common, these malignancies can present with epigastric pain and should be considered, especially in an elderly patient with new-onset symptoms.
Mesenteric Ischemia: This condition involves insufficient blood flow to the intestines and can cause severe abdominal pain out of proportion to the physical examination findings, often without clear relation to eating.