You are greatly narrowing the rooms that will meet your criteria...there only so many rooms that are on the top floor, facing the lake in 50's. But, you may be able to get what you want. I have to say that in all my stays at WDW, about 20+ at this point, my quietest stays have been at POP...and that's 5 stays there. The only quieter stay I've had was when I was at BWV, at the very end of a hall...about a 2 min walk from the elevators. That room was ridiculously quiet.
I have never had a noise issue at POP. I did have a preferred room, in 70's, that was on the ground floor..a lot of foot traffic in that room, with subsequent noise from people just chatting as they walked by.
My best stay at POP?? 60's, bldg 4, 4th floor, facing the lake. It was an incredible room...quiet, short walk to bus/food court, and faced the lake. I just loved it there.