Almost certainly, because there is not a middleman dealing with your order. With these guys you get a bikefit and a decent consultation (in English)... and they answer their phones/emails. It's an (expensive) option.
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;
It would, but cost would be offset by going to a UK fitter first.
Incidentally I am quite flexible, but I don't have much saddle-to-bar drop on my bikes. And yet I'm still quite low, at least by normal standards. Back well past 45 degrees etc.
http://www.racerrosabicycles.co.uk/
^ these guys will get you what you want built in Italy for ~ 800.
Half that (and some hunting) buys an excellent condition or NOS frame with a story and some history – you might have to have a threaded fork.