Single Skin Brick Exterior Wall Leaks Heavy Rains

Hi... I am new to this forum and have come here seeking some advice. I have a small 2 family across the street from the Atlantic Ocean. The house was built in 1943 and is pretty solid. My problem is that the front external wall is made up single skin brick with no sheating, no moisture barrier, no weep holes, no drip flashing. Just brick, king studs, and drywall. When you cut out a section of drywall, you seek the back of the bricks! The house was built during WWII and it is my understanding this method of cheap construction was common in England during the War to save materials. During normal rains, I have no problems. However, during Northeasters, heavy wind driven rain, or rains lastign 2-3 days, I will get leakage from the two first floor windows. Windows have soldier courses, with steel lintel under them. Water appears after several hours and stains appear down the side of the windows. The floor below will leak into the basement. Water stains are on the rim joist, but both that and the sill appear OK. Again, this is just under the windows. Bricks were painted in the 1950s, so I must paint the bricks. Just painted with Valspar Duramax, but still get leakage. Is there anything at all that can be done? Any advice will be appreciated.