I was under the impression that the old frame doesn't have that much saddle to bar drop on account of those classic bar whose brake lever is halfway down, especially considering that they don't show a lots of seatpost;
Stop throwing spanners. You don't have to set them up as in 1990.
My Concorde is 55.5cm square and it works great for winter with a 130mm stem. I have more post showing than was the norm years ago, but less than on most compact geo bikes.
Rychtarski/Orlowski would be cheaper no?
The NOS route is very good too. You have a 'working spine' as miro puts it ..