Hello Ben, It looks like 3/8 BSP both sides. I put the vernier on it to check and it came out at 0.65″ ish and the book for 3/8 BSP is 0.656. My gauge is a smiths unit so it should be the same but check anyway. As for the quarter light rubbers I think they were a one piece L section part that was made to fit the quarter light opening. I will check and look up some old pictures. Window rubbers for our cars are virtually non existent , I am fast approaching needing a complete set but no one does our sizes. I will check on what the quarter light should be, kind regards, Charles 
Hello Ben, It looks like 3/8 BSP both sides. I put the vernier on it to check and it came out at 0.65" ish and the book for 3/8 BSP is 0.656. My gauge is a smiths unit so it should be the same but check anyway. As for the quarter light rubbers I think they were a one piece L section part that was made to fit the quarter light opening. I will check and look up some old pictures. Window rubbers for our cars are virtually non existent , I am fast approaching needing a complete set but no one does our sizes. I will check on what the quarter light should be, kind regards, Charles