HI FROM LANGLEY BC,
You could still find a decent frame for your gruppo despite all these years. Pick a frame where all your Dura Ace Ex parts will fit. Probably a nice steel Italian made frame could do them justice.
I have a vintage steel bike which I assembled from scratch during the 70's-80's. It has a 27"x 1" Araya rim and weighs heavy. What does this bike proud is its parts. From top to bottom: seatpost, stem, headset, brakes, crank, front and read derailleur, hubs are all Dura Ace EX. I just slightly modified it to suit the current genre by replacing the original brake levers with a newer Dura Ace lever and also replacing the original pedals with a clipless one. (I bought and adaptor for this). You will have countless hours admiring this old gruppo. I still do.