Leather Blazer - # 712

The blazer was of very high quality. I have four other 44S leather blazers. They all fit well. The size of this blazer fits well in the shoulders but does not fit around the waist / belly area. The size 44S is smaller around the waist that any of my other jackets. I want to buy additional blazers but do not know what size to order. Please advise if two inched can be added to the waist of the blazer when ordered as a 44S.