I see you want a 70-72, but a few days ago I saw a supposed original engine southern US '69 442 ragtop advertised online up here somewhere?. Seemed kind've pricey around 35 thou?...and who know's what it's like??.
That fixer upper '71 442/W30 ragtop in the 'Rotting Musclecars' thread yesterday may be available...and real??.
Good luck!.
~ Pete